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WETLAND ASSESSMENT LAKE WASHINGTON VIEW ESTATES .(King County Parcel No. 3224059081 ) Renton, Washington Prepared for: Heritage Homes, Inc. March 20, 2007 �1lo Project No. 06028 �E a�� A Qt� Evergreen Aquatic Resource Consultants, LLC 4020 Lake Washington Boulevard, Suite 101, Kirkland, Washington 98033 Phone (425) 576-0333 FAX (425) 576-0360 March 20, 2007 Project No 06028 Heritage Homes, Inc. 4325 SW 323 d Street Federal Way, Washington 98072 Attention: Mr. Von Karl Inman Subject: Wetland Assessment Lake Washington View Estates (King County Parcel No. 3224059081) Renton, Washington Dear Mr. Inman: Evergreen Aquatic Resource Consultants, LLC (Evergreen) is pleased to present the following Wetland Assessment. This document presents the findings of an October 2006 wetland delineation survey completed by Evergreen on the above -referenced subject site located in Renton, Washington. Evergreen completed the work presented within this report using the wetland identification and reporting methodologies as required by the City of Renton. Additionally, this report has been prepared in recognition of current City of Renton regulations and guidelines. Please contact me should you have any questions or comments regarding the information presented in the attached document. Sincerely, EVERGREEN AQUATIC RESOURCE CONSULTANTS, LLC Kirkland, Washington Frederick L. Huston, Jr. Principal Biologist Enclosure WETLAND ASSESSMENT Lake Washington View Estates (King County Parcel No. 3224059081) Renton, Washington Prepared for.• Heritage Homes, Inc. 4325 SW 323`" Street Federal Way, Washington 98072 Prepared by.• Evergreen Aquatic Resource Consultants, LLC 4020 Lake Washington Boulevard, Suite 101 Kirkland, Washington 98033 March 20, 2007 Project No. 06028 Lake Washington View Estates (King County Parcel No. 3224059061 Wetland Assessment TABLE OF CONTENTS Page 1.0 INTRODUCTION....................................................................................................................................1 2.0 SCOPE OF WORK AND METHODOLOGY..........................................................................................1 2.1 Authorization............................................................................................................ .......1 2.2 Literature Review...........................................................................................................................1 2.3 Wetland Delineation Survey..........................................................................................................1 2.4 Limitations......................................................................................................................................1 3.0 RESULTS OF THE WETLAND DELINEATION SURVEY.....................................................................2 3.1 Literature Review...........................................................................................................................2 3.1.1 Soils................................................................................................................................... 2 3.1.2 Wetlands............................................................................................................................ 2 3.2 Wetland Delineation Survey..........................................................................................---......2 3.2.1 Overview............................................................................................................................2 3.2.2 Wetland 1...........................................................................................................................2 3.2.3 Wetland 2...........................................................................................................................3 3.2.4 Wetland 3...........................................................................................................................3 3.2.5 Upland................................................................................................................................4 4.0 REGULATORY DISCUSSION...............................................................................................................4 4.1 Local Regulations..........................................................................................................................4 4.2 State and Federal Regulations......................................................................................................6 5.0 PROPOSED PROJECT.........................................................................................................................6 5.1 Description and Purpose of Proposed Project.............................................................................. 6 6.0 SUMMARY.............................................................................................................................................6 7.0 REFERENCES.......................................................................................................................................7 LIST OF TABLES Table 1 Preliminary Renton Wetland Classifications and Standard Buffers ..............................5 LIST OF APPENDICES Appendix A Figures Appendix B Wetland Delineation Data Forms March 20, 2007 Evergreen Aquatic Resource Consultants, LLC Page Lake Washington View Estates (King County Parcel No. 3224059061 Wetland Assessment 1.0 INTRODUCTION On October 2 and October 3, 2006, Evergreen Aquatic Resource Consultants, LLC (Evergreen) completed a wetland delineation survey on a 5-5-acre parcel (King County Parcel No. 3224059081) located in Renton, Washington. The purpose of Evergreen's wetland assessment was to identify and document on -site wetlands, if any. Adjacent off -site properties within 100 feet of the subject site were reviewed as practical for the potential presence of wetland habitat. This report summarizes the findings and interpretations of the October 2006 wetland assessment. 2.0 SCOPE OF WORK AND METHODOLOGY 2.1 Authorization Heritage Homes, Inc. (Heritage) granted authorization to proceed with completion of the wetland delineation survey on September 27, 2006. Evergreen completed the work presented in this report in general accordance with the related "Professional Services Agreement" and the work order identified as 'Work Order 1". This document has been prepared for the exclusive use of Heritage, their authorized agents, and/or their consultants. 2.2 Literature Review Prior to completing the on -site wetland delineation, Evergreen reviewed published soil information to gather previously documented information on known soil characteristics within and/or in the immediate vicinity of the subject site. Additionally, readily available natural resource inventory maps and related documentation were referenced to determine the existence of previously identified aquatic resource features on and/or within the immediate vicinity of the subject site. 2.3 Wetland Delineation Survey The October 2006 on -site wetland delineation survey was completed using the methodologies defined in the Washington State Wetlands Identification and Delineation Manual (Washington State Department of Ecology [Ecology] 1997) and the Corps of Engineers (Corps) Wetland Delineation Manual (Environmental Laboratory 1987). The boundaries of on -site areas determined to satisfy the technical criteria for classification as wetland were marked in the field using sequentially numbered, pink "wetland delineation" flagging. Non-random, representative sample plots were established and marked in the field using sequentially numbered, blue fluorescent flagging. Hansen Surveying (Hansen) surveyed and mapped all wetland boundary points and sample plots established on -site by Evergreen. Figure 1 (Appendix A) presents existing wetland -related survey information for the site. Standard wetland delineation data forms used to record the information collected at established sample plots are included in Appendix B. 2.4 Limitations The results and conclusions presented in this report represent an analysis of information provided by Heritage, their representatives, and/or their consultants, together with information independently gathered by Evergreen during the course of this study. The determination of critical area location and classification is an inexact science, subject to regulatory agency review. Consequently, the work and results presented in this document represent Evergreen's best professional opinion based on the described technical methodologies, professional experience, regulatory requirements and guidance known to be in effect at the time of study completion, and any noted site, weather, and time -of -year considerations. Evergreen makes no other warranty, expressed or implied. As, Evergreen cannot guarantee the results of regulatory agency review of the work presented in this document, Evergreen recommends that the results of this March 20, 2007 Evergreen Aquatic Resource Consultants, LLC Page 1 Lake Washington View Estates (King County Parcel No. 3224059081 Wetland Assessment study be presented to the appropriate regulatory agencies for review and approval prior to any property transfer, preliminary design, and/or construction activities. 3.0 RESULTS OF THE WETLAND DELINEATION SURVEY 3.1 Literature Review 3.1.1 Soils Soils within the subject site are mapped as Alderwood gravelly sandy loam, 6% to 15% slopes (AgC), Indianola loamy fine sand, 4 to 15 percent slopes (InC), and Norma sandy loam (No) (USDA 2007). Alderwood soils are comprised of well -drained soils formed on uplands in glacial deposits and typically have a weakly consolidated to strongly consolidated substratum at 24 to 40 inches. Indianola soils are comprised of somewhat excessively drained soils that formed in sandy, recessional, stratified glacial drift. Norma soils are poorly drained soils that formed in alluvium and generally occur along streams and in basins on glaciated uplands. The Alderwood and Indianola soils have no local or national classification as hydric soils (USDA 2001; USDA 1991). However, Norma soils are classified locally and nationally as hydric soils (USDA 2001; USDA 1991). 3.1.2 Wetlands The National Wetlands Inventory (NWI) map for the local area identifies a riverine lower perennial unconsolidated bottom permanently flooded (R2UBH) wetland (May Creek) located within the vicinity of the subject site (USFWS 1988). The Washington State Department of Fisheries (WDF) identifies the subject site as occurring within the South Lake Washington Sub -Basin of the Lake Washington Basin. Furthermore, WDF (1975) identifies May Creek as Stream Number 08-0282. The City of Renton's (Renton) wetland inventory map does not identify any wetlands as occurring on the subject site (Renton 2005). 3.2 Wetland Delineation Survey 3.2.1 Overview The approximately 5.5-acre subject site is located in Renton, Washington. May Creek and Interstate 405 form the northern and eastern boundaries of the subject site, respectively. Residentially zoned parcels are located south of the project site and Lake Washington Boulevard North comprises the western site boundary. The general on -site topography slopes from south to north, although the portion of the site adjacent to May Creek is topographically flat. As a result of the October 2006 wetland delineation survey, three wetlands (Wetland 1, Wetland 2, and Wetland 3) were delineated within the limits of the subject site. At the time of Evergreen's fieldwork, the maximum ambient air temperature was approximately 65 °F and sky conditions were generally fair. The total rainfall for the local area during the months of July, August, and early September 2006 was less than average. Figure 1 (Appendix A) presents existing wetland -related survey information for the site. 3.2.2 Wetland 1 Wetland 1 is located in the western portion of the subject site (Figure 1, Appendix A) and supports palustrine scrub -shrub wetland habitat. Wetland 1 is approximately 0.14-acre (6,093 square feet [fe]) in total area and does not extend off -site. The basis of the wetland determination for Wetland 1 included the observation of hydric soil field indicators and sediment marks and water staining on vegetation and detritus within the interior portions of the wetland. Wetland boundary points established for Wetland 1 consist of WB 1-1 through WB 1-14, WB 1-14A, WB 1-15, WB 1-15A, and WB 1-16 through WB 1-20. Sample plots established for Wetland 1 consist of Plots 1 and 2 (Figure 1, Appendix A). March 20, 2007 Evergreen Aquatic Resource Consultants, LLC Page 2 Lake Washinaton View Estates (King Countv Parcel No. 3224059061) Wetland Assessment Although shallow seasonal groundwater may provide a portion of the hydrology supporting Wetland 1, it appears that a majority of the supporting hydrology for this wetland is stormwater runoff originating from the portion of Lake Washington Boulevard North. These stormwater flows discharge to Wetland 1 via a ditch located along the east side of Lake Washington Boulevard North. Although there is the potential that these stormwater flows eventually discharge to May Creek, Evergreen did not observe any discharge at the time of a brief review of the site on November 9, 2006 that occurred during a period of heavy precipitation throughout the Puget Sound lowlands. Dominant plant species observed within Wetland 1 consist of Himalayan blackberry (Rubus discolor) and Sitka willow (Salix sitchensis). Other plant species observed within Wetland 1 include Pacific willow (Salix lasiandra), red alder (Alnus rubra), lady fern (Athyrium filix-femina), sword fern (Polystichum munitum), and pig -a -back plant (Tolmeia menziesii). Soils observed within Wetland 1 were generally a black (10YR 2/1) sandy silt loam above a dark olive gray (5Y 3/2) sand which was overlying a very dark gray (2.5Y 3/1) silt loam. Soil mottle colors observed ranged from a very dark brown (7.5YR 2.5/3) to a yellowish brown (10YR 5/6 to 10YR 5/8) in color. These mottles ranged from few to common in abundance, fine to medium in size, and faint to distinct in contrast. Field indicators of wetland hydrology observed within Wetland 1 included sediment marks and water staining on vegetation and detritus within interior portions of Wetland 1. The lack of observed soil saturation, shallow groundwater, and/or surface water was likely due to the time of year the wetland delineation survey was completed. 3.2.3 Wetland 2 Wetland 2 has an on -site area of approximately 0.08-acre (3,535 fe). This wetland is located in the south-central portion of the subject site (Figure 1, Appendix A). Wetland 2 supports palustrine scrub - shrub wetland habitat and it appears that contiguous wetland habitat may extend off -site to the south into a maintained lawn of a single-family residence. Mounds of soil occur throughout many portions of Wetland 2 and an abandoned roadbed constructed of soil bisects Wetland 2 in roughly a southwest to northeast orientation. The basis of the wetland determination for Wetland 2 included the observation of hydric soil field indicators as well as the presence of indicators of wetland hydrology such as wetland drainage patterns. Wetland boundary points established for Wetland 2 consist of WB 2-1 through WB 2-19. Sample plots established for Wetland 2 consist of Plots 3 and 4 (Figure 1, Appendix A). Wetland 2 is dominated almost exclusively by Himalayan blackberry; however, other species such as lady fern and sword fern do occur within isolated, discrete portions of this wetland. Soils observed within Wetland 2 were generally a black (10YR 2/1) to very dark brown (10YR 2/2) sandy silt loam over a very dark grayish brown (10YR 3/2) to dark brown (10YR 3/3) to brown (10YR 4/3) to dark olive brown (2.5Y 3/3) sandy silt loam. Soil mottles, which were only observed within the lower soil layer, were generally strong brown (7.5YR 4/4) to dark yellowish brown (10YR 4/6) in color. These mottles were many in abundance, faint in appearance, and fine in size. Field indicators of wetland hydrology observed within Wetland 2 included saturation of surface soils and wetland drainage patterns. Wetland 2 appears to be hydrologically isolated. 3.2.4 Wetland 3 Wetland 3, which supports palustrine forested wetland habitat, is located in the eastern portion of the subject site (Figure 1, Appendix A). Contiguous wetland habitat extends off -site to the south for an undetermined distance. The on -site portion of Wetland 3 is approximately 0.53-acre (22,926 fe) in size. The basis of the wetland determination for Wetland 3 included the observation of shallow inundation within the vicinity of two drainages located interior to the wetland, saturation of surface soils within March 20, 2007 Evergreen Aquatic Resource Consultants, LLC Page 3 Lake Washinaton View Estates (Kina Countv Parcel No. 3224059081) Wetland Assessment portions of the wetland, wetland drainage patterns, and field indicators of hydric soil. Wetland boundary points established for Wetland 3 consist of WB 3-1 through WB 3-43. Sample plots established for Wetland 3 consist of Plots 5 and 6 (Figure 1, Appendix A). In addition to shallow seasonal groundwater, Wetland 3 also receives hydrologic support from a small stream that flows on -site from the south and another drainage that lies entirely interior to Wetland 3. Based on localized topography and the lack of evidence of defined channels or scouring, it does not appear that surface flows within these aquatic features discharge to May Creek. Dominant plant species observed within Wetland 3 include red alder, salmonberry (Rubus spectabilis), and Himalayan blackberry (Rubus discolor). Other common plant species observed within at least portions of Wetland 3 include lady fern, skunk cabbage (Lysichiton americanum), reed canarygrass (Phalaris arundinacea), bittersweet nightshade (Solarium dulcamara), pig -a -back plant, and stinging nettle (Urtica dioica). Non-native ivy (Hedera spp.) is the dominant species in the off -site portions of Wetland 3. Soils observed within Wetland 3 were generally a very dark brown (10YR 2/2) sand over a black (10YR 2/1) sandy silt loam. Field indicators of wetland hydrology observed within Wetland 3 included shallow inundation within the vicinity of the above -referenced drainages, saturation of surface soils within portions of the wetland, and wetland drainage patterns. 3.2.5 Upland On -site upland habitats generally support a forested canopy over a shrub community comprised primarily of Himalayan blackberry. Black cottonwood and red alder are the dominant tree species in on -site upland habitats with bigleaf maple (Acer macrophyllum), western redcedar (Thuia plicata), and western hemlock (Tsuga heterophylla) also being present on -site. In addition to Himalayan blackberry, other shrub species noted within on -site upland habitats include vine maple (Acer circinatum), hazelnut (Corylus cornuta), Indian plum (Oemleria cerasiformis), sword fern (Polystichum munitum), and red elderberry (Sambucus racemosa). Soils observed within areas determined to support upland habitat were generally sandy silt loams that ranged in color from very dark grayish brown (10YR 312) to dark brown (10YR 313) to brown (10YR 4/3) to olive brown (2.5Y 4/3). No soil mottling was observed within soils determined to support upland habitat and no field indicators of wetland hydrology were apparent within on -site areas determined to support upland habitat. Sample Plots 2, 4, 6, and 7 (Figure 1, Appendix A) were established to document representative conditions within on -site upland habitats. 4.0 REGULATORY DISCUSSION 4.1 Local Regulations Development activities within the subject site fall under the local jurisdiction of the City of Renton (Renton). Development standards and requirements related to wetlands located within the subject site are subject to the policies contained in Title IV - Development Regulations, Chapter 4-3 (Environmental Regulations and Overlay Districts) of the Renton Municipal Code (RMC). The RMC categorizes wetlands based on the parameters such as the presence of listed animal and plant species (and/or the presence of associated essential habitat), the overall size of the wetland, the structure and diversity of the wetland plant community, the presence of permanent open water within the wetland, and past disturbances to the wetland. Based on the information presented in the RMC, preliminary wetland classifications and standard buffer widths for each wetland identified by Evergreen are included in Table 1. March 20, 2007 Evergreen Aquatic Resource Consultants, LLC Page 4 Lake Washington View Estates (King County Parcel No. 3224059081) Wetland Assessment TABLE 1 PRELIMINARY RENTON WETLAND CLASSIFICATIONS AND STANDARD BUFFERS WETLAND HABITAT AREA CATEGORY" BUFFER"'E RATIONALE a Stormwater originating from Lake Washington Boulevard North is routed into the wetland; and Wetland 1 Palustrine Scrub -Shrub 093 (6,093c2ft)e 3B 25 Feet . The dominant plant species in the plant community is a non-native plant species (Himalayan blackberry). R Soils within the wetland have been impacted by past land uses; and Wetland 2 Palustrine Scrub -Shrub (3,535c2e 535 ft) 3c 25 Feet • The dominant plant species in the plant community is a non-native plant species (Himalayan blackberry). Acre 02, 0 • The wetland does not satisfy the criteria for Wetland 3 Palustrine Forested (29 26 ft) 2 50 Feet categorization as a Category 1 wetland or a Category 3 wetland. A Preliminary pending concurrence by applicable regulatory agencies. B Per RMC 4-3-050.M.1.a.iii.(e) (Renton 2005). c Per RMC 4-3-050.M.1.a.iii.(a)(1) and RMC 4-3-050.M.1.a.111.(c) (Renton 2005). ° Per RMC 4-3-050.M.1.a.li.(a) (Renton 2005). E Per RMC 4-3-050.M.6.c (Renton 2005). March 20, 2007 Evergreen Aquatic Resource Consultants, LLC Page 5 Lake Washington View Estates (King County Parcel No. 322405908 f) Wetland Assessment 4.2 State and Federal Regulations Under Section 404 of the Clean Water Act (CWA), the Corps may also regulate on -site development activities. Additionally, under Section 401 of the CWA, the Washington State Water Pollution Control Act (Chapter 90.48 Revised Code of Washington [RCW]), Federal Coastal Zone Management Act, and/or the Washington State Shoreline Management Act (Chapter 90.58 RCW), Ecology may also regulate on -site development activities. Consequently, should final site plans propose impacts to on -site wetlands and/or buffers, Evergreen recommends that the Corps, Ecology, and all other applicable regulatory agencies be contacted to determine the necessity of obtaining other permits and/or approvals for the project. 5.0 PROPOSED PROJECT 5.1 Description and Purpose of Proposed Project The current development proposal (Figure 2, Appendix A) includes the subdivision of the existing parcel, the construction of 13 single-family residences, the construction of a roadway which terminates in a cul- de-sac to provide access to 12 of the lots (access to the remaining lot will be via Meadow Avenue North), and the construction of other infrastructure associated with the overall development. As proposed, no direct impacts to wetlands and associated buffers, or other aquatic resources, will occur. 411 17, I'T, LI -. Yi On October 2 and October 3, 2006, Evergreen completed a wetland delineation survey on the above - referenced 5.5-acre parcel located in Renton, Washington. The result of Evergreen's study was the identification of three on -site wetlands. Wetlands 1 and 2 were preliminarily classified as Category 3 wetlands requiring a 25-foot buffer while Wetland 3 was preliminarily classified as a Category 2 wetland requiring a 50-foot buffer. March 20, 2007 Evergreen Aquatic Resource Consultants, LLC Page 6 Lake Washington thew Estates (King County Parcel No. 3224059061) Wetland Assessment 7.0 REFERENCES Chapter 90.48 Revised Code of Washington Washington. Chapter 90.58 Revised Code of Washington. Washington. 2006. Washington State Legislature, Olympia, 2006. Washington State Legislature, Olympia, Environmental Laboratory. 1987. Corps of Engineers wetlands delineation manual. Technical Report Y- 87-1, U.S. Army Corps of Engineer Waterways Experiment Station, Vicksburg, Mississippi. Hansen Surveying. (Hansen). 2006. Drawings dated November 20, 2006 and January 9, 2007. Renton, City of. 2005. Renton Municipal Code (RMC), Title IV - Development Regulations, Chapter 3 (Environmental Regulations and Overlay Districts), Sub -Chapter 050 (Critical Areas Regulations). Effective December 12, 2005. United States Department of Agriculture (USDA). 2007. Web Soil Survey (WSS). Natural. Resources Conservation Services (NRCS). htt ://websoilsurve .nres.usda. ov/a /WebSoilSurve .as x. Accessed January 15, 2007. United States Department of Agriculture (USDA)_ 2001. Hydric soils list, King County Area, Washington: detailed soil map legend. Natural Resources Conservation Services (NRCS). http://www.wa.nrcs.usda.govltechnical/soils/hydric lists/h dsoil-wa-657. df. Last updated October 30, 2001. Accessed January 15, 2007. United States Department of Agriculture (USDA). 1991. Hydric soils of the United States. Soil Conservation Service (SCS). Miscellaneous Publication Number 1491. Washington D.C. United States Fish and Wildlife Service (USFWS). 1988. National Wetlands Inventory, Mercer Island, Washington 7.5-minute quadrangle map. Washington State Department of Ecology (Ecology). 1997. Washington State Wetland Identification and Delineation Manual. Publication No. 96-94. Olympia, Washington. Washington State Department of Fisheries. 1975. A Catalogue of Washington Streams and Salmon Utilization, Volume 1, Puget Sound Region. Olympia, Washington. March 20, 2007 Evergreen Aquatic Resource Consultants, LLC Page 7 APPENDIX A Figures 141sAWA0800 RM AV IM nfu (SONV113W SNOLLKINOO SNIISIX3 090-ga (ROmw cao-ols (IMP) RRL "I am 1491aam pmwm uagwp4wm am am 1 ml *uznnmo3 ownma *Ipnbv uaw6joA3 em (00690VUE 'ON -130blVd) S31V1S3 MBIA NOIDNIHSVM 3XYI I aLval i i --------------- ---------------- - ------------ �. �. ell 0- f* tk' M 'A' x 0 IN T77 Ar`1f7r-17- Pwu :uO,d" 1f owi 10i AUVNIWl-l3ad 48069M= 'ON 1301AVd) LODZJ O S31V.LS3 M31A NOIJNIHSVAA 3NVI 9 own-915 (SZb) � fff0-9L5 (sn) I�l ££ 86 uW6u14seM'puervN 101 a41nS'1.smilJON pjeAolnoig uW6ul4seM;la'1Rot, LL :)71 's;ue;insuo:) awnosab 31jenbd ueaa6aan3 ash t M ..49.0t.10 S ¢ AM M .49.01.10 5 i gi 1 r' X APPENDIX B Wetland Delineation Data Forms DATA FORM ROUTINE WETLAND DETERMINATION (1967 COE Wetlands Delineation -Manual) Project Site: Lake Washin ton View Estates Date: October 3, 2GOO A IicantlOwner: Heritage Homes, Inc. (Applicant) County: Kin Investigator Frederick L. Huston, Jr. State: Washington Do Normal Circumstances exist on the site? ® Yes ❑ No Community ID: Wetland 1 - Wetland Is the site significantly disturbed (Atypical Situation)? ❑ Yes ® No Transact ID: Is Area a Potential problem Area? if needed, explain on reverse ILI JYes IN, lNo Plot ID: Plot 1 VEGETATION Dominant Plant Species Stratum Indicator Dominant Plant Species Stratum Indicator 1 Sitka willow shrub FACW a 2 Himalayan blackberry shrub FACU 9 3 laqy lam herb FAG 10 4 11 5 12 6 13 7 14 Percent of Dominant Species that are OBL, FACW or FAC (excluding FAC-): 50 percent (Pacific willow - 70% and Himalayan blackberry - 60%) Remarks: None. HYDROLOGY ❑ Recorded Data (describe in Remarks) Wetland Hydrology Indicators: Stream Lake, or Tide Gauge Ptimary Indicators: econdW Indicators 2 or more re /ed : ❑ Aerial Photographs ❑ I Inundated ❑ Oxidized Root Channels in Upper 12" ❑ 1 Other ❑ Saturated in Upper 12 inches Water -Stained Leaves No recorded date available ❑ Water Marks ❑ Local Soil Survey Data Field Observations: ❑ Drift Lines ❑ FAC-Neutral Test Depth of Surface Water: none in. ® Sediment Deposits ❑ Other (explain in remarks Depth to Free Water in Pit: I none In- ® I Drainage Patterns in Wetlands Depth to Saturated Soil: I none In. Remarks_ No direct observations of wetland hydrology (e.g., inundation, soil saturation, etc.) were noted; however, the primary indicators noted above were observed. SOILS Map Unit Name Series and Phase): Norma silt loam Drainage Class: poorly drained Circle Taxonomy (Subgroup): Typic Huma ue is Field Observations Confirm Mapped Type? Yes TNO Profile Description: Depth inches Horizon Matrix Color Munsell Moist)Munsell Mottle Colors Moist Mottle Abundance! Size/Contrast Texture, Concretions, Structure, etc_ 0-9 A 1 OYR 211 sandySilt loam 9-12 81 5Y 312 10YR 5/6 to 10YR 5/8 few, fine, faint sand 12-16 82 2.5Y 311 2.5Y 5/3 common medium distinct silt loam H dric Soil Indicators: ❑ Histosol ® Reducing Conditions © High Organic Content in Surface Layer in Sandy Soils ❑ Histic Epipedon ® Gle ed or Low-Chroma Colors ® Listed an National Hydric Soils List ❑ Sulfidic Odor I ❑ Concretions ® Listed on Local H dric Soils List ® A uic Moisture Regime I ❑ Organic Sireaking in Sandy Soils I ❑ I Other (explain in remarks Remarks: Positive field indicators of hydric soils were observed. WETLAND DETERMINATION Hydrophytic Vegetation Present? I ❑ Yes ® I No I Is this Samplinq Point Within a Wetland? 1 ® 1 Yes I ❑ I No Wetland Hydrology Present? ® Yes I❑ No Hydric Soils Present? ® Yes I❑ No Although the vegetation criterion was not strictly satisfied, this area meets the criteria for consideration as wetland based on observations of field Remarks; indicators of hydric soils and wetland hydrology. Previous guidance related to the lack of hydrophytic vegetation allows this area to meet the criteria for consideration as wetland. DATA FORM ROUTINE WETLAND DETERMINATION (1967 COE Wetlands Delineation Manual) Project Site: Lake Washington View Estates Date: October 3, 2t106 Applicant/Owner Heritage Homes Inc. (Applicant) County: Kin Investigator Frederick L. Huston Jr. State: Washington Do Normal Circumstances exist on the site? ® Yes ❑ No Community ID: Watland 1 - Upland Is the site significantly disturbed (Atypical Situation)? ❑ Yes ® No Transact ID: Is Area a Potential Problem Area? if needed, ex lain on reverse ❑ Yes ® No Plot ID: Plot 2 VEGETATION Dominant Plant Species Stratum Indicator Dominant Plant Species Stratum Indicator 1 black cottonwood tree FAC 6 2 bi leaf maple tree FACU 9 3 red alder tree FAC 10 4 Himalayan blackberry shrub FACU 11 5 sword lam shrub FACU 12 6 13 7 14 Percent of Dominant Species that are OBL, FACW or FAC (excluding FAC-): 50 percent (black cottonwood - 55% and Himalayan blackberry - 70%) Remarks: None. HYDROLOGY ❑ Recorded Data (describe in Remarks) Wetland Hydrology Indicators: ❑ Stream, Lake, or Tide Gauge Pnmar Indicators: ndary Indicators 2 or more re wired : ❑ I Aerial Photographs ❑ Inundated ❑ Oxidized Root Channels in Upper 12" ❑ Other ❑ Saturated in Upper 12 inches ❑ Water -Stained Leaves ® No recorded data available ❑ Water Marks ❑ Local Soil Survey Data Field Observations: ❑ Drift Lines ❑ FAC-Neutral Test Depth of Surface Water. none In. ❑ Sediment Deposits ❑ Other ex lain in remarks Depth to Free Water in Pit: none In. ❑ Drainage Pattems in Wetlands Depth to Saturated Soil: none In. Remarks: No direct observations of primary or secondary indicators of wetland hydrology were noted. SOILS Map Unit Name Series and Phase): Norma silt loam Drainage Class: poody drained Circle Taxonomy (Subgroup): Typic Huma ue is Field Observations Confirm Mapped Type? Yes I No Profile Des cri tion: Depth inches Horizon Matrix Color Munsell Moist Mottle Colors Munsell Moist Mottle Abundance) Size/Contrast Texture, Concretions, Structure, etc. 0-2 A 10YR 2/1 sandy silt loam 2-10 61 10YR 3/2 sandy silt loam 10-16 B2 10YR 3/3 sand Hydrio Soil Indicators: Histosol ❑ Reducing Conditions ❑ High O anic Content in Surface Layer in Sandy Soils ❑ Histic E i don ❑ Gle ed or Low-Chroma Colors ❑ Listed on National H dric Soils List ❑ ILI I Sulfidic Odor ❑ Concretions ❑ 1 Listed on Local Hydric Soils List I A uic Moisture Regime Organic Streakirp in Sandy Soils ❑ Other ex lair in remarks Remarks: No positive field indicators of hydric soils were observed. WETLAND DETERMINATION HArophllic Vegetation Present? I ❑ I Yes I ED I No Is this Samplinq Point Within a Wetland? I ❑ I Yes 1 ® 1 No Wetland Hydrology Present? ❑ Yes ® No Hydric Soils Present? ❑ Yes ® No Remarks: None of the three criteria were satisfied. DATA FORM ROUTINE WETLAND DETERMINATION (1987 COE Wetlands Delineation Manual) taro ect Site: lake Washi ton View Estates Date: October 3, 2006 ApplicanVOwner Heritage Homes, Inc. (Applicant) County: Kin Investigator Frederick L. Huston, Jr. State: Washington Do Normal Circumstances exist on the site? ® Yes ❑ No Community ID: Wetland 2 - Wetland Is the site significantly disturbed (Atypical Situation)? ❑ Yes ® No Transect ID: Is Area a Potential Problem Area? it needed, explain on reverse ❑ Yes ® No Plot ID: Plot 3 VEGETATION Dominant Plant Species Stratum Indicator Dominant Plant Species Stratum Indicator 1 red alder tree FAG a 2 Himalayan blackberry shrub FACU 9 3 salmonberry shrub FAG+ 10 4 reed Ganarygrass herb FACW+ 11 6 lady fem herb FAC 12 e 13 7 14 Percent of Dominant Species that are QBL, FACW or FAC (excluding FAC-): 67 percent (red alder - 70%, Himalayan blackberry - 90%, and reed canarygrass - 20%) Remarks: None. HYDROLOGY ❑ Recorded Data (describe in Remarks) Wetland Hydrology Indicators: ❑ Stream, Lake, or Tide Gauge Pnmary Indicators: econdary Indicators 2 ormare rotired : ❑ Aerial Photographs ❑ I Inundated I Oxidized Root Channels in Upper 12" ❑ Other ElSaturated in Upper 12 inches I Water -Stained Leaves ® No recorded data available ❑ Water Marks 1 Local Soil Survey Data Field Observations: ❑ Drift Lines ❑ FAC-Neutral Test Depth of Surface Water: none In- ❑ Sediment Deposits ❑ Other (explain in remarks Depth to Free Water in Pit: I none In. ® Drainage Patterns in Wetlands De th to Saturated Soil: I surface in - Remarks: Primary indicators of wetland hydrology as noted above were observed. SOILS Mae Unit Name Series and Phase): Norma silt loam I Drainage Class: poorly drained Circle Taxonomy (Subgroup): Typic Huma ue is I Feld Observations Conlirm Map22d Type? Yes No Profile Des cri lion: Depth inches Horizon Matrix Color Munsell Moist Mottle Colors Munsell Moist Mottle Abundance/ Size/Contrast Texture, Concretions, Structure, etc. 0-10 A 1 OYR 211 to 10YR 212 sandy silt loam 10-16 B 10YR 313 to 2-SY 3I3 7.5YR 414 to 1 OYR 416 common, fine, distinct sandy silt loam H dric Soil Indicators: ❑ Histosol ❑ Reducing Conditions ❑ High Organic Content in Surface Layer in Sandy Soils ❑ Histic Epipedon ❑ Gle ed or Low-Chroma Colors ❑ listed on National H dric Soils List ❑ I Sulfidic Odor ❑ I Concretions ❑ Listed on Local Hydric Soils List ® 1 A uic Moisture Regime ❑ I fl anic St —akin in Sandy Soils ❑ Other a lain in remarks Remarks: Although the matrices do not necessarily satsisfy the field criteria for classification as hydric soils, the soils met the technical definition of hydric based an the presence of surficial saturation. WETLAND DETERMINATION Hydrophylic Vegetation Present? ®1 Yes 1 ❑ 1 No Is this Samplino Point Within a Wettand? ® Yes ❑ No Wetland Hydrology Present? ®I Yes 1 ❑ No Hydric Soils Present? I ® I Yes ❑ No Remarks: All three criteria were satisfied. DATA FORM ROUTINE WETLAND DETERMINATION (1987 COE Wetlands Delineation Manual) Project Site: I Lake Washington View Estates Date: October 3 2006 IicanUOwner: I Heritage Homes, Inc. (Applicant) County: Kin Investigator: I Fraderick L. Huston, Jr. State: WashiQMon Do Normal Circumstances exist on the site? ® 1 Yes 1 ❑ 1 No Communi ID; Wetland 2 - Upland Is the site significantly disturbed (Atypical Situation ? ❑ 1 Yes 1 ® 1 No Transect ID: Is Area a Potential Problem Area? it needed, explain on reverse I ❑ I Yes 1 ® 1 No Plot ID: Plot 4 VEGETATION Dominant Plant Species Stratum Indicator Dominant Plant Species Stratum Indicator 1 red alder tree FAC e 2 Himalayan blackberry shrub FACU a 3 10 4 11 5 12 B 13 7 1 1 1 14 Percent of Dominant Species that are OBL, FACW or FAC (excluding FAG-): 50 percent (red alder- 56% and Himalayan blackberry - 90%) Remarks: None. HYDROLOGY ❑ Recorded Data (describe in Remarks) Wetland Hydrology Indicators: ❑ Stream, Lake, or Tide Gauge Pfimary indicators: Secondary Indicators 2 or more re uired ❑ Aerial Photographs ❑ Inundated ❑ Oxidized Root Channels in Upper 12* ❑ I Other ❑ Saturated in Upper 12 inches ❑ Water -Stained Leaves ® No recorded data available ❑ Water Marks ❑ Local Soil Survey Data Field Observations: ❑ Drift Lines ❑ FAC-Neutral Test Depth of Surface Water. none In. ❑ I Sediment Deposits ❑ Other (explain in remarks Depth to Free Water in Pit: none In. ❑ Drainage Patterns in Wetlands Depth to Saturated Soil: none In. Remarks: No direct observations of primary or secondary indicators of wetland hydrology were noted. SOILS Map Unit Name Series and Phase): I Norma silt loam Drains a Class: poorly drained Circle Taxonomy Su ro T is Huma ue s Field Observations Confirm Mapped Type? Yes No Profile Des cri lion: Depth inches Horizon Matrix Color Munsell Moist Mottle Colors Munsell Moist Mottle Abundance/ Size/Contrast Texture, Concretions, Structure, etc, 0-2 A 10YR 2i2 to 10YR 3i2 sandy silt loam 2-16 8 10YR 313 to 10YR 413 sandy silt loam H dric Soil Indicators: ❑ Histosol ❑ Reducing Conditions ❑ 1 High Organic Content in Surface La ar in Sandy Soils ❑ 1 Histic E i edon ❑ Gle ed or Law-Chroma Colors ❑ 1 Listed on National Hygric Soils List ❑ I Sulfidic Odor ❑ Concretions ❑ Listed on Local Hydric Soils List ❑ I A uic Moisture Regime ❑ I Organic Streaking in Sandy Soils ❑ Other (explain in remarks Remarks: No positive field indicators of hydric soils were observed. WETLAND DETERMINATION Hydrophytic Ve etation Present? 1 ❑ 1as ® No I Is this Sampling Point Within a Wetland? ❑ Yes No Wetland Hydrology Present? I Q I Yes 1 ® 1 No Hydric Soils Present? I ❑ I Yes 1 ® 1 No Remarks: None of the three criteria were satisfied. DATA FORM ROUTINE WETLAND DETERMINATION (1987 COE Wetlands Delineation Manual) Project Site: I Lake Washington View Estates Date: October 3 2006 Applicant/Owner I Heritage Homes, Inc. (Applicant) County: King Investigator Frederick L. Huston, Jr. State: Washington Do Normal Circumstances exist on the site? ® Yes ❑ 1 No Communi ID: Wetland 3- Wetland Is the site significantly disturbed (Atypical Situation? ❑ Yes ® 1 No Transect ID: Is Area a Potential Problem Area? if needed a ain on reverse ❑ I Yes 1 ® 1 No Plot ID: Plot 5 VEGETATION Dominant Plant Species Stratum Indicator Dominant Plant Species Stratum Indicator 1 red alder tree FAC e 2 salmonberry shrub FAC+ s 3 Himala an blackberry shrub FACU 10 4 sword lem shrub FACU 11 s reed canarygrass herb FACW+ 12 s giant horsetail herb FAC 13 7 1 lady fem herb FAC 14 Percent of Dominant Species that are OBL, FACW or FAC (excluding FAC-): 100 percent (fed alder - 85%, salmonberry - 20%, and reed canarygrass - 20%) Remarks: None. HYDROLOGY ❑ Recorded Data (describe in Remarks) Wetland Hydrology Indicators: ❑ Stream Lake, or Tide Gauge Primary Indicators: S dM Indicators 2 or more required): ❑ Aerial Phologra hs ❑ Inundated ❑ 1 Oxidized Root Channels in Upper 12" ❑ Other ❑ Saturated in Upper 12 inches ❑ Water -Stained Leaves No recorded data available ❑ Water Marks ❑ 1 Local Soil Survey Data Field Observations: ❑ Drift Lines ❑ FAC-Neutral Test Depth of Surface Water; I none In- El I Sediment Deposits ❑ Other (explain in remarks Depth to Free Water in Pit: I none In. ® Drainage Patterns in Wetlands Depth to Saturated Soil: 14 In - Remarks: In addition to the primary indicatorof wetland hydrology noted above, the soils were saturated at approximately 14 inches. SOILS Map Unit Name Series and Phase): Norma silt loam Draina a Class: poorly drained Circle Taxonomy Su rou : Typic Huma ue is Field Observations Confirm Mapped Type? I Yes No Profile Descri tion: Depth inches Horizon Matrix Color Munsell Moist Mottle Colors Munsell Moist Mottle Abundance/ Size/Contrast Texture, Concretions, Structure, etc. 0-14 A 10YR 212 sand 14-16 B 10YR 211 sandy silt loam Hydric Soil Indicators: ❑ Histosol ❑ Reducing Conditions ❑ High Organic Content in Surface Layer in Sandy Soils ❑ Histic E i edon ® Gle ed or Low-Chroma Colors ® Listed on National Hydric Soils List ❑ Sulfidic Odor El I Concretions Listed on Local H dric Soils List ® LA uic Moisture Regime ❑ I Organic Streaking in Sandy Soils ❑ Other ex lain in remarks Remarks: Positive field indicators of hydric soils were observed. WETLAND DETERMINATION Hydrophytic Vegetation Present? ® 1 es ❑ No Is this Sampling Point Within a Wetland? ® Yes ❑ No Wetland Hydrology Present? ® I Yes ❑ No H dric Soils Present? ® Yes ❑ No Remarks: All three criteria were satisfied. DATA FORM ROUTINE WETLAND DETERMINATION (1987 COE Wetlands Delineation Manual) Project Site: I lake Washi2gton View Estates Date: October 3, 2006 licant/Owner. I Hedts a Homes Inc.(Applicant) County: King Investigator I Frederick L. Huston, Jr. State: Washington Do Normal Circumstances exist on the site? 1 1 Yes 1 ❑ 1 No Community ID: Wetland 3 - U land Is the site significantly disturbed (Atypical Situation)? 1 1 Yes ® No Transact ID: Is Area a Potential Problem Area? if needed, a in on reverse ❑ I Yes ® No Plot ID: Plot 6 VEGETATION Dominant Plant Species Stratum Indicator Dominant Plant Species Stratum Indicator 1 red alder tree FAG 8 2 bi leaf maple tree FACU s 3 salmonber tree FAG+ 10 a i -a-back plant herb FAG 11 5 12 6 13 7 14 Percent of Dominant Species that are OBL, FACW or FAC (excluding FAC-): 100 percent (red alder - 70 % and salmonberry - 70%) Remarks: None. HYDROLOGY ❑ Recorded Data (describe in Remarks) Wetland Hydrology Indicators: ❑ Stream, Lake, or Tide Gauge Pnmary Indicators econdaw Indicators 2 or more Mwrs ❑ 1 Aerial Photographs ❑ Inundated ❑ Oxidized Root Channels in Upper IT ❑ Other ❑ Saturated in Upper 12 inches ❑ Water -Stained Leaves ® No recorded data available ❑ Water Marks ❑ Local Soil Survey Data Field Observations: ❑ Drift Lines ❑ FAC-Neutral Test Depth of Surface Water: none In. ❑ Sediment Deposits Other ex sin in remarks Depth to Free Water in Pit: none In. ❑ Drainage Patterns in Wetlands Depth to Saturated Soil: none In. Remarks: No direct observations of primary or secondary indicators of wetland hydrology were noted. SOILS Map Unit Name Series and Phase): Norma sill loam Draina a Class: poorty drained Circle Taxonomy Su rou : Typic Huma ue is Feld Observations Confirm Mapped Type? Yes No Profile Descri Oon: Depth inches Horizon Matrix Color Munsell Moist Mottle Colors Munsell Moist Mottle Abundance/ Size/Contrast Texture, Concretions, Structure, etc. 0-7 A 10YR 312 sandy silt loam 10-16 B 2.5YAl 3to 10YR 313 sandy loam Hyddc Soil Indicators: ❑ Histosol ❑ Reducing Conditions ❑ High O anic Content in Surface Layer in Sandy Soils ❑ Histic E i don ❑ Gle ed or Low Chroma Colors Listed on National H dric Solls List ❑ I Sulfidic Odor ❑ Concretions ❑ Listed on Local Hyddc Soils Llst ❑ I Aquic Moisture Regime 0 1 Or anic Streaking in Sandy Soils ❑ I Other (explain in remarks Remarks: No positive field indicators of hydric soils were observed. WETLAND DETERMINATION HydrophytiG V etation Present? ® Yes ❑ 1 No I Is this Sampling Point Within a Wetland? ❑ Yes ® No Wetland Hydrology Present? ❑ Yes ® No H dric Soils Present? ❑ Yes ® No Remarks: Only one of the three criteria was satisfied. DATA FORM ROUTINE WETLAND DETERMINATION (1987 COE Wetlands Delineation Manual) Project Site: Lake Washinaton View Estates Date: October 3 2006 kcant/Owner: Heritage Homes, Inc. (Applicant) County: Ki Investigator: Frederick L. Huston, Jr. State: Washington Do Normal Circumstances exist on the site? ® Yes I ❑ I No Community ID: Upland Is the site significantly disturbed (8telcal Situation)? I ❑ I Yes ® 1 No Transact ID: Is Area a Potential Problem Area? ifneeded, a ain on reverse2 1 ❑ Yes ® 1 No Plot ID: Plot 7 VEGETATION Dominant Plant Species Stratum Indicator Dominant Plant Species Stratum Indicator 1 black cottonwood tree FAC a 2 red alder tree FAC 9 3 Himalayan blackberry shrub FACU 10 4 11 5 12 8 1 13 7 1 1 14 Percent of Dominant Species that are OBL, FACW or FAG (excluding FAC-): 56 percent (black cottonwood - 80 % and Himalayan blackberry - 100%) Remarks: None. HYDROLOGY ❑ Recorded Data (describe in Remarks) Wetland Hydrology Indicators: ❑ Stream, Lake, or Tide Gauge Pnrnary Indicators: ndety lrxdcators 2 or more m re : ❑ Aerial Photographs ❑ Inundated ❑ Oxidized Root Channels in Upper 12" ❑ Other ❑ Saturated in Upper 12 inches ❑ Water Stained Leaves ® No recorded data available ❑ Water Marks ❑ Local Soil Survey Data Field Observations: ❑ Drift Lines ❑ FAC-Neutral Test Depth of Surface Water: none In. ❑ Sediment Deposits ❑ Other axplain in remarks Depth to Free Water in Pit: none In. ❑ Drainage Patterns in Wetlands Depth to Saturated Soil: none In. Remarks: No direct observations of primary or secondary indicators of wetland hydrology were noted. SOILS Map Unit Name Series and Phase); Norma silt loam Drainage Class: poorlydrained Circle Taxonomy Su rou Typic Huma ue is Field Observations Confirm Mapped Type? I Yes I No Profile Description: Depth inches Horizon Matrix Color Munsell Moist Mottle Colors Munsell Moist Mottle Abundance/ Size/Contrast Texture, Concretions, Structure, etc. 0-2 A 1OYR 2/2 to 10YR 3(2 sandy silt loam Hydric Soil Indicators: ❑ Histosoi ❑ Reducing Conditions ❑ High Organic Content in Surface Layer in Sandy Soils ❑ 1 Histic Epipedon ❑ Gle ed or Low-Chroma Colors ❑ Listed on National H dric Soils List ❑ Sulfidic Odor ❑ Concretions Listed on Local Hydric Soils List ❑ I A uic Moisture Regime ❑ I Organic Streaking in Sandy Soils ❑ I Other (explain in remarks Remarks: No positive field indicators of hyddc soils were observed. WETLAND DETERMINATION Hydrophytic Vegetation Present? ❑ Yes ® No I Is this Sampling Point Within a Wetland? 1 ❑ 1 Yes 1 ® 1 No Wetland Hydroloqv Present? Yes I ® I No H dric Soils Present? I ❑ I Yes I ® I No Remarks: None of the three criteria were satisfied. NEIGHBORHOOD DY -L AIL MAP 1':/I C1 1�! prA ONNING OR - •_ 0 A Zf 200 } 100 200 \µ _zz p 5m r\T P Q _ f i - N. '+ � 40TH 57- W - S7 T r L— ` 493_i - _� c-=p �c _ Y5. F6 a J 104 y G i 0 _- WAS `` OE-'/ELGP WING APR - 3 2007 DECEIVED Site Development Associates, LLC Project Location: 42XX Lake Washington Blvd. N. Renton, WA Prepared For: Offs Engineers 13932 SE 1591' Place Renton, WA 98058 Prepared By: Ken McIntyre, P.E. Site Development Associates, LLC 10117 Main Street Bothell, WA 98011 Date: March 23, 2007 Project Number. 107-023-07 FAWCETT LAKE TECHNICAL INFORMATION REPORT Project Location: 42XX Lake Washington Blvd. N. Renton, WA Prepared For: Offe Engineers 13932 SE 159' Place Renton, WA 98058 Prepared By: Ken McIntyre, R.E. Site Development Associates, LLC 10117 Main Street Bothell, WA 98011 Date: March 23, 2007 Project Number: 107-023-07 G;7 FAWCETrLAKE TECHNICAL INFORMATION REPORT TABLE OF CONTENTS SECTION 1— PROJECT OVERVIEW • Project Overview SECTION 2 - CONDITIONS & REQUIREMENTS SUMMARY • Summary of Core Requirements • Summary of Special Requirements • Summary of Additional Requirements SECTION 3 — OFFSITE ANALYSIS • Task 9 — Study Area Definition and Maps Task 2 — Resource Review • Task 3 — Field Inspection Task 4 — Drainage System Description and Problem Description Task 5 — Mitigation of Existing or Potential Problems • Appendix 3-A — Offsite Mapping • Appendix 3-8 — Resource Review Documents SECTION 4 — FLOW CONTROL AND WATER QUALITY FACILITY ANALYSIS & DESIGN • Existing Site Hydrology • Developed Site Hydrology • Performance Standards • Flow Control System • Water Quality System . Appendix 4-A — Hydrologic Background Information SECTION 6 — CONVEYANCE SYSTEM ANALYSIS S DESIGN SECTION 6 — SPECIAL REPORTS & STUDIES SECTION 7 — OTHER PERMITS SECTION 8 — ESC ANALYSIS & DESIGN SECTION 9 — BOND QUANTITIES AND FACILITY SUMMARIES SECTION 10 — OPERATIONS & MAINTENANCE MANUAL FAWCETT LAKE TECHNICAL INFORMATION REPORT SECTION 1 PROJECT OVERVIEW FAWCETT LAKE TECHNICAL INFORMATION REPORT PROJECT OVERVIEW The Fawcett Lake plat proposes the subdivision of a single parcel totaling 5.53 acres, into 13 single-family residential lots along with a large open space area to accommodate wetlands and buffer areas which currently exist on the site. The project site is located in Section 32, Township 24 North, Range 5 East of the Willamette Meridian. More specifically, the project lies on the east side of Lake Washington Boulevard, north of N. 40'" St. and south of May Creek. The site topography can generally be described as steep, falling toward May Creek, which lies along the north boundary of the site. The existing vegetation consists mainly of brush, blackberry bushes, and some trees. Wetland areas currently occupy the northwest comer of the site, as well as a large area near the center of the property. No structures currently exist on the project site. The site proposes the construction of twelve lots near the west end of the site, which will be accessed from Lake Washington Boulevard, and a thirteenth lot at the southeast comer of the site, which will be accessed from N. 40' Street. FAWCETT LAKE TECHNICAL INFORMATION REPORT King County Department of Development and Environmental Serviicea TECHNICAL INFORMATION REPORT (TIR) WORKSHEET owner: le Engineer. Ken McIntyre ny: Site DevekprA t Associates aJPhone: 10117 Main Street Bothell, WA 96011 0 Subdivision ❑ Short Subdivision ❑ Grading ❑ commerclal ❑ Other: ❑ DFW IPA ❑ CDE 404 ❑ DOE Dam Safety ❑ FEMA Fkoodplair ❑ COE Wetlands Community: Cedar River 1 Lake Washin Drainage Basin: May Creek ❑ River: 0 Stream: May Creek ❑ CAM[ Slream Reach ❑ Delnles Lake. 0 Steep Slopes: (over 40% slopes on-stte) FAWCETT LAKE TECHNICAL INFORMATION REPORT ❑ Shorilne Management ❑' Rockery slnwturai Vaults ❑ Wrer (see below) ❑ Floodplain: ❑� Wetlands: (on -site) ❑ Seeps/Springs ❑ High Groundwater Table ❑ Groundwater Recharge ❑ Other: Soil Type Alderwood (AgC) Indianola (InC) Norma (No ❑ Additional Sheets Attached REFERENCE Ch. a - Downstream Analysis Cl Additional Sheets Attached 0-3O% 0-40% a-60% Slopes MINIMUM ESC REQUIREMENTS DURING CONSTRUCTION ❑' Sedimentation Facllltles ❑� StaNlized Constru=n Entrance ❑� Perimeter Runoff Control ❑ Clearing and Grading Restrki<lons ❑� Cover Practices ❑r Construction Sequence ❑ Other FAWCETT LAKE TECHNICAL INFORMATION REPORT Erosion Potential Moderate Slight - Moderate Slight Erosive Velocities MINIMUM ESC REQUIREMENTS AFTER CONSTRUCTION ❑� Stabilize Exposed Surface Remove and Restore Temporary E5C Facilities ❑� (lean and Remove All Silt and Debris ❑ Ensure Operation of Permanent Faciliies ❑� Flag Limps of SAO and open space preservation areas ❑ Other ❑ Gras Lined Channel ❑ Tank ❑ lrifaGabon D Pipe Symm ❑ vaar ❑ aepres!*w ❑ Opel, chwel ❑ Ener9y Dwwtor ❑ Flow DN)wsM ❑"pow [�) Wetland ❑ waiver ❑ Wet Pond 0 Stream ❑ Rega%al I)Mnbon Method of Analysis KCRTS CompensabonlMitigation of Eliminated Site Storage Underground_ Vardt Brief Description aF Collection and conveyance via pipe system, flow control b treatment through underground Vault System Operation_ �. Facility Related Site Limitations Reference Facility ❑ Cast in Now Vault 0 Retairi tQ Wall © RWcNY > W HIP ❑ Stu Mral on Steep Slope Limitation or a civil engineer under my supervision have visited the site_ Ac*ual site conditions as observed were incorporated into this rorksheet and the attachments. To the best of my knowledge Bra' ormation provided here is accurate. /� /�/ FAWCETT LAKE TECHNICAL INFORMATION REPORT PROJECT LOCATION d a. w a I� NE 44TH ST —{ zw J(n O U w � Z J a f'O .y IOU 5E 88TH ST COleman PO t N 30TH ST 9� May Creek Lj �d IV z �' w z { w Z Z Ld a w w m c m c w n w Z 01 O w °n m N J S 4 1 NKJ Np ' FAWCETT ALKE N.T.S. town _...W___ - -_ - cale 08-�1x-Q7 Sete Development Assockdea. LLC DataVICINITY 0 107-023-07 Ong Aas.�� roe 10 ••• M w.w�,. ,.. MAP pure O. � Project NO. \ a.,,,o..+.\ I fY7(nffol\ n? z_m 710 n _f:-01 A.., i. 5 C m m 40• SOIL SURVEY OF KING COUNTY AREA, WASHINGTON Fawcett Lake . Meters 0 15 30 60 11SU�1 N.d,ral Smm a Web Soil Survey I.I Cm*wrrttor.%"ke National Cooperative Soil Survey Feet 0 45 90 180 270 360 3123a007 Page l of 3 SOIL_ SURVEY OF KING COUNTY AREA, WASHINGTON 0 O ..l Z C M a C M 4k MAP LEGEND MAP INFORMATION Soil Map units 0 Clues Source of Map: Natural Resources Conservation Service Q Detailed counties Web Soil Survey URL: http:IAvebsoilsurvey.nres.usda.gov C� Detailed States Intestate Highways Coordinate System: UTM Zone 10 Roads Soil Survey Area: King County Area, Washington —+--t— Rails Spatial Version of Data: 1 AW— I water Soil Map Compilation Scale: 1:24000 Hydmgraphy AMATATAX Escarpment, bedrock vnvnvAv Escarpment, non -bedrock ti ti tn.ti. Gulley nntnmuai Levee .......... Slope kv Blowout ® Borrow Pit Clay Spot • Depression, dosed Eroded Spot X Gravel Plt Gravelly Spot Guby A Lava Row 0 LandfIll Map comprised of aerial images photographed on these dates; +I. Marsh or Swamp 7/10/1990; 7/18/1990 0 Miscdlarreous Vvater v Rook Outcrop + Salina Spot Sandy Spot 33 Slide or Slip 0 Sinkhole p+ sodK Spot The orthophoto or other base map on which the soil lines were compiled and * Soc Area digitized probably differs from the background imagery displayed on these maps. o Stony spot As a result, some minor shifting of map unit boundaries mW be evident ® Perennial VAler US[)A Natural Repwre ! Wkt Spot am eoruer AM sa.ice Web Soil Survey 1.1 National Cooperativc Soil Survey 3/23/2007 Page 2 of 3 Soil Survey of King County Area, Washington Fawcett Lake Map Unit Legend Summary King County Area, Washington Map Unit Symbol Map Unit Name Acres in AOI Percent of AOI Inc Indianola loamy fine sand, 4 to 1.1 30.2 15 percent slopes Wit, vr- - + USDA Nmnd 2--w— Web Soil Sam" 1.1 � C....vad..se.k. National CooperativeSoil Survcy FIGURE 4 (CONTINUED) Soil Properties (per USDA Soil Survey for King County) Alderwood gM%I! r sandy loam. 6 to 15 percent slopes (A-QQ. This soil is roiling. Areas are irregular in shape and range from 10 to about 600 acres in size. Permeability is moderately rapid in the surface layer and subsoil and very slow in the substratum. Roots penetrate easily to the consolidated substratum where they tend to mat on the surface. Some roots enter the substratum through cracks. Water moves on top of the substratum in winter. Available water capacity is low. Runoff is slow to medium, and the hazard of erosion is moderate. Indianola loamy fine sand. 4 to 15 percent slopes (InC) This undulating and rolling soil has convex slopes. It is near the edges of upland terraces. Areas range from 5 to more than 100 acres in size. Permeability is rapid. The effective rooting depth is 60 inches or more. Available water capacity is moderate. Runoff is slow to medium, and the erosion hazard is slight to moderate. Norma sandy f loam (No). This soil occurs as strips 25 to 300 feet wide. Slopes are less than 2 percent. Areas are level or concave and range from 1 to about 100 acres in size. Permeability is moderately rapid. The seasonal water table is at or near the surface. In drained areas, the effective rooting depth is 60 inches or more. In undrained areas, rooting depth is restricted. The available water capacity is moderately high to high. Runoff is slow, and the erosion hazard is slight. Stream overflow is a severe hazard in places. FAWCETT lAK€ TECHNICAL INFORMATION REPORT SECTION 2 CONDITIONS & REQUIREMENTS SUMMARY FAWCETT LAKE TECHNICAL INFORMATION REPORT SUMMARY OF SPECIAL REQUIREMENTS Special Requirement #9 — Other Adopted Area -Specific Requirements No other adopted area -specific requirements were found to apply to this project site. • Special Requirement #2 — Flood Hazard Area Delineation The 100-yr floodplain for May Creek is shown in the "King County Hydrographic Information" exhibit, which is contained in Appendix 3-13 of this report. The 100-yr floodplain extends onto the subject property, but does not extend as far south as the proposed lots. Since the project site lies on a significant hillside, the ground elevation of the lots closest to May Creek will likely be raised, further reducing the flood hazard. Special Requirement #3 — Flood Protection Facilities No flood protection facilities lie on, near, or downstream of the subject property. • Special Requirement #4 — Source Control The project is a residential development, and is exempt from source control provisions. * Special Requirement #5 — Oil Control The project is a residential development, and is exempt from oil control provisions. SUMMARY OF ADDITIONAL REQUIREMENTS The site does not appear to be subject to any additional requirements beyond the 8 Core Requirements and 5 Special Requirements listed above. FAWCETT LAKE TECHNICAL INFORMATION REPORT SUMMARY OF CORE REQUIREMENTS Core Requirement #? - Discharge at Natural Location The project site currently discharges to Mays Creek, which defines the northern boundary of the site_ In the developed condition, runoff which is collected on -site will be conveyed to a discharge point along Mays Creek. Core Requirement #2 — Offshe Analysis An off -site analysis is included in Section 3 of this report. • Core Requirement #3 — Flow Control Flow control will be provided by an underground detention/treatrnent vault. Further discussion of the vault and design calculations are included in Section 4 of this report • Core Requirement #4 - Conveyance Sytem The project proposes an underground pipe network to convey stormwater to the underground detention vault and discharge to Mays Creek. Conveyance system sizing is addressed in Section 5 of this report. • Cone Requirement #5 — Erosion $ Sediment Control Temporary erosion and sediment control is addressed in Section 8 of this report. Core Requirement #6 — Maintenance & Operations Maintenance and operations of the proposed stormwater facilities is addressed in Section 10 of this report. • .Core Requirement #7 - Financial Guarantees $ Liabilities Construction for all stormwater facilities will be bonded and insured as required by the City of Renton. Come Requirement #8 — Water Quality Stormwater treatment will be provided via wetpool storage within the underground detention vault. Details of the proposed stormwater quality measures are provided in Section 4 of this report. FAWCETT LAKE TECHNICAL INFORMATION REPORT SECTION 3 OFFSITE ANALYSIS FAWCETT LAKE TECHNICAL INFORMATION REPORT a Sensitive Areas Folio King County Sensitive Areas Folio information is now available through King County's online "]-Map' service. Appendix 3-S contains a map titled "Sensitive Areas", which depicts the sensitive areas that King County has delineated in the vicinity of the project site. The map depicts May Creek as being a sensitive area stream, and the east end of the project is depicted as an erosion hazard area. No other sensitive areas exist on the site. • Road Drainage Problems No Road Drainage Problems have been identified near the project site. • USDA Soil Survey for King County A USDA soil survey map has been included as Figure 4 of this report. The map was generated from the Natural Resources Conservation Service's website, and areas of Alderwood, Indianola, and Norma Soils. The proposed development area at the west end of the site consists primarily of Alderwood soils with a small portion of Indianola soils. The single lot that is proposed at the east end of the subject property appears to be underlain by Norma Soils. Alderwood and Norma soils are generally considered to be "Till" soils, with little capacity for infiltration. Indianola soils are generally considered to be "Outwash' soils, with some infiltration capacity. The hydrologic analysis for this project will assume that Till soils underly all proposed development areas, since this appears to be a case for a large majority of the proposed development area. The fringes of the proposed development shown to be underlain by Outwash soils are likely very small areas, and likely to consist of a mix of Till and Outwash soils, and may not be fully suitable for infiltration. Migrating River Studies No migrating river studies are pertinent to this project FAWCETT LAKE TECHNICAL INFORMATION REPORT Task 3 - Field inspection The project site was visited on the morning of March 23, 2007. The conditions at the time of the visit were cloudy and cool, with some light precipitation having occurred the previous night. A trickle of surface runoff was present in some of the road -side ditches and on -site drainage conveyances. The project site itself is relatively steep, but well stabilized with vegetation such as blackberries and miscellaneous brush. Homes are currently being constructed off -site, near the southeast corner of the parcel. No erosion or sediment transportation from these projects was noticeable on the project site. At the west end of the project site, a road -side ditch was located. The ditch runs along the east side of take Washington Boulevard N., and discharges to May Creek. A small, swale also appears to extend through the brush near the west edge of the site. This swale combines with the road -side ditch near the midpoint of the west property line. Based on the topography observed during the site visit, it appears that the entire site drains directly to May Creek. May .Creek continues westerly, beneath a road bridge on Lake Washington Boulevard N., then southwesterly for approximately 1,200 feet before discharging to Lake Washington. Task 4 - Drainage System Description and Problem Description The drainage system investigation began at the project site. A road -side ditch exists along the property's frontage with Lake Washington Boulevard. The ditch appears to be well vegetated and relatively clear of debris. No significant erosion or sediment accumulation were noted in the ditch. Photo #1 (Looking North along property's frontage with Lake Washington Blvd.) FAWCETT LAKE TECHNICAL INFORMATION REPORT The road -side ditch along Lake Washignton boulevard appears to be triangular in shape, approximately T wide and 2' deep. Near the middle of the site's frontage, flow from the ditch enters a 12" concrete pipe, which then discharges to another ditch, as shown in Photo #2. Photo #2 (Looking South along property's frontage with lake Washington Blvd.) Flow from the road -side ditch appears to combine with a small Swale that extends through the on -site brush (see Photo #3). The combined channel enters a ravine that discharges into May Creek at the north edge of the site. FAWCETT LAKE TECHNICAL INFORMATION REPORT '� � . ��,� ._} ��� ..' 4 � � , J �" . d� M � �R9 �'7 � � �� ' P-• i �` � Sr'. � " y i � r � ,��. �+ x z-r i' �^i 1� �+lE _ � 1i`�� �: �P+: ` � E.. �.�. _ - ` � r <, �f " �- - '•l' �� After surface runoff from the site enters May Creek, it flows westerly beneath a bridge along Lake Washington Boulevard. May Creek continues westerly beneath a railroad bridge (see Photo #5), then turns southwesterly and continues to Lake Washington. Photo #5 (Looking west at May Creek f m Lake Washington Blvd.) Photo #6 (Looking upstream at May Creek. approximately 500' downstream of project site) FAWCETT LAKE TECHNICAL INFORMATION REPORT Task 5 - Mitigation of Existing or Potential Problems No existing problems were noted during the drainage investigation. The proposed frontage improvements will remove the existing road -side ditch along the site's frontage with Lake Washington Boulevard, so a conveyance system will need to be installed beneath the proposed curb -line as part of the frontage improvements. Rock stabilization should be installed at this system's outfall above May Creels. FAWCETT LAKE TECHNICAL INFORMATION REPORT APPENDIX 3-A OFFSITE MAPPING FAWCETT LAKE TECHNICAL INFORMATION REPORT J&KM9CounV Study Area Ma a3, !F X6, 3224059W 9 3724D59r U Lake WashTstgiav� n 3 ! ° 227_ _ 3 249Q#6_ . 3224ASHDB3 - 3?l#dS97d2 '3 3224059D4 '° . 3224OMW J- -.: �39427nDODS {�f'��Lf .�- -r' 33427000a7 t '3S421OW27 IW700534 3U27LD53f1 3361.!. �334270b'S4b �� . 33427:10iS33 33427a0ss4 '33421C0077 33427UDt?5 334270D532 > 331230083Q t »: 93a2]!ODD70' RIP 33f27DGyl13 �34?70012Q 3342760M 3U?741D6i:S 394270049t) 331270a4D5 33 2T00'JA0 4 3ilOil r t41 tY� Y „',�3t27D04fC 33427ou4ts LBgorld /a! Cdunky 6autdary streota �t Lakes drrd towers Contours iM tWrtj Ntp ., i—.•" Streewu ��t0ei9 max'' "mum �% Incorparaled Area Loco Aarcats �jMa7r0 jATwrAt/ information included on this map teas been compiled by ling County staff from a variety of spumes and is subject to cnange wmmi noom. rnmg wunry kes no representations or warranties, express or implied. as to accuracy, completeness, timdse ine. or rights to the use of such information. King County hail nol be liable far any general, special, indirect, incidental, or consequential damages including, but not limited to, lost revenues or lost profits resulting from use or misuse of the information oontahad on this map. Any sale of this map or information on this map is prohibtted except by written permission of King arc• 27A_' r7 Cn,— Wkr r'' rintw MAP _ Sfnrmwafwr rhftn'!lwww.metmkc ncwiGII]MAP1 APPENDIX 3-13 RESOURCE REVIEW DOCUMENTS FAWCETT LAKE TECHNICAL INFORMATION REPORT V • Horne I News I Services I Comments Lsuarch PARCEL REPORT Districts and Development Conditions for Parcel number: 3224059081 BY LAW THIS INFORMATION MAY NOT BE USED FOR COMMERCIAL PURPOSES, Administrative Districts and Areas Address Not Available Jurisdiction Renton Zipcode 98056 King County Council District (_CQUNGIL..IN TRANSITION) Council District:9 Council Member: Reagan Dunn Phone: (206) 296-1009 Web site School District Renton #403 Fire District Not Available Water District None Sewer District None Water and Sewer District None Water Service Planning Area Renton, City of Tribal Lands No Plannina Desionatinns K(ng County Zoning Not Available Comprehensive Plan Land Use Not Available Urban Growth Area Urban Community Planning Area Green River Valley _UDincorm.a-ted Area CQunNI None P-Suffix Conditions None Kroll Map Page 457 Thomas Guide Map Page 626 Agricultural Production District No Forest Production District No Roads MPS Zone 111 Transportation__Concurrency_ZQne 562 Environmental Areas Drainage Basin May Creek Rural Clearing Limits Apply Not Available Wate hecfi Nwg Cedar River t Lake Washington WRIA Name Cedar,Sammamish WRIp 1rium_h}X 8 Wetland None mapped 100-Year FloQd Plain Yes Coal Mine Hazards None mapped Erosion Hazards Yes Landslide Hazards None mapped Seismic Hazards None mapped Critical Aquifer Recharge Area None mapped DDES Permitting Information lessor Property Characteristics Report ZtiQQrn to Parcel - iMAP (High,$pped Internet Connection Zgom to P_ r l- Parcel V n m t C n .� The infomtation included on this report has been complied by King County staff from a variety of sources and Is subject to change without notice. King County makes no representations or warranties, express or implied, as to accuracy, completeness, timeliness, or rights to the use of such inforrnatlon. King County shall not be liable for any general, special. Indirect, incidental, or consequential darnages lnctuding, but not limited to, lost revenues or lost profits resulting from the use or rrisuse of the information contained on this report_ Any sale of this report or information on this report Is proMbited except by written perudsslon of King County. This report was generated: 3/23/2007 12.46:14 PM Enter a 10 digit Parcel Number. or Enter an address: Search King-GwW I GIS Center I News I Ser_v_ices I Comments I Search 8y visiting this and other King County web pages, YOU expraseiy agree to be bound by terrns and conditions of the site. "11 JOINS PANEL 0675 LIMIT OF OETAILEO STUDY �N 1 t/ }ZONE X Y %/. May .s;� 4aTrI s� RE E T x i NORTH 36TH STREET NORTH NORTH 137TH STREET z z q NORTH NORTH 3151'H STREET NORTH 35TH STREET a a NORTH 34TH STREET `Xd MEADOW NORTH z Lu L z C tu n ,ZONE AE APPROXIMATE SCALE IN FEET 500 0 500 NA71OKU FM lMSORAMCE PROSRA61 FIRM FLOOD INSURANCE RATE MAP KING COUNTY, WASHINGTON AND INCORPORATED AREAS PANEL 664 OF 1725 1SEE MAP INCEX FCA PANELS NOT PRINIED} OOWMIINny. I'11RdBER PANE. A1FRX ova cowry. WA4000OMIM SAE" awn au r nE1fmM.0+ OF swop =4 r LEAP NUMBER 53030164 F 32 MAP REVISED: MAY 16,1"S UNIN Federal Emergeocy Manopment Agency 1 This is an olAeid copy of a poPoon of Ute above reAoreneed Aaod map. It was extracted using F-MIT On-Une. This map does mat redact changes or amendment which may hwm boon made subsequent to the date on the d�, ride block. For the latest product inkxmwbon about National Wow insurance Ploprem Road maps check the FEMA Flood Map Store at wwmmse-fama.gov W KM9CmintY - Lake WaShingron WOaoos f , rr =24&%*W 33 ! 322�EJ�Di(k! a222._sOd9dB3 ' ' J;exroead7 sxrmfr33MMrtte �70000e ."711s3l2rpouse - 3s+aroovr� � �i2r(iW7s rr � 7A0 7oas3�. � �2�K5! ._�.._ .... .�. `' �: aoei „ {{� a�urnoe �� � 20 yt}9A06KY1GwMt r -Aw 1270r71i0 J342TOGsi r00�(65- 3Ci0yda i27 i alrs L*gond ttlydragiupis Apr ® a: arerwarl T ACTM Aar �: snallaei! Logo s: o.d.w� �J C-Nft15ouidary _3 POPOCiM 3:dlwwiih rrn HW—yf �fi 10 Yom Ffoadptaln is: wly,aPtslw. 10" owl* tlrairrags Lileaa acid Lac" Rivers�.:.. 11 gas&le Shialne _3 � 17: dr,a..,ct... $� tri6orpOrited Alin $1Mdld fifdisf 1pnp CauntY YMtiter Resom* tnv&Mwy Arias f A- i nfonrratlon included on this map has been conpiled by King County staff from a variety of scuroes and is subject to change wfflux t notice- iGng County = no repmsentatians or warranties, express or implied, as to accura rYy. completeness, timeliness, or rVft to the use of such infom►alion. King County II not be liable for arty general, special, indirect. Incklental, or oonsequenlisl damages including, but not ling tad to, lost revenues or lost prords resulting is use or misuse of the information contained an this map. Any sale of thls nap or Information on to map is prohloitad except by wrlitart permission of King rnty. e: 3-252007 Source: Ki1g County MAP - Hydrogrephic Infomlation (http:t www.rnetrokc gowtGlSlrMAP) Sensitive Areas E AI$r rJ W As" �yr�Ailt► �iA�f�+r�� rr Like trilAshirrrfton fiT Renton fF Fr _ - ... - _ _ }` a �. ' •r 3 1! ---aa - - - :. Y, P. ---------�"'c'Y J.X. IC} sees tit crowtr;' ( 01111musilillmi r Legend `! Cai++t!► 8otattltFly CbM2sawAxmd 99 SAO coal liWry aYis Chm3 ® SAO SeiWW t Incorporated Area a SAO Erosion titraa�e f —1 Lakes and large lxivers I w4tmw Steams ArtwGb { bmnrkel Migration Hazard Arias - . lent MODERATE V Parr4fs 2fAU SAO Stream SAO Watland /40' Cb=3 ® SAO Landslide c4m2Ptiw�n included on this map has been compiled by King County staff from a variety of sources and is subject to change without notice. King County no representations or warrantles, express or Implied, as to accuracy, completeness, timeliness, or rights to the use of such information. King County k-I-OF-3 t be liable for any general, special, indired• incidental, or consequential damages including, but not limited to. lost revenues or lost profits resultargfrom or misuse of the information oontained on this map. Any sale of this map or information on this map is prohibited except by written pemtisslon of King -26.2007 Source: Ki Coon NAP - Sensitive Areas :IMrww-metrokc. vIGIS/iMAP 3.2.2 KCRTS1RUNOFF FFLES METHOD— GENERATING TIME SERIES SCS Soil Type k ,.. K SCS Hydrologic Sol! Group KCRTS Soil Group Notes derwood B, C, A D C Till Arents, Alderwood Material jAmB, AmC C Till Arents, Everett Material An B Outwash 1 Beausite BOC, BeD, BeF C Till 2 Bellingham Bh D Till 3 Briscot Br D Till 1 3 Buckle Bu D Till 4 Eadrnont Ea D Till 3 Ed wick Ed C Till 3 Everett vB, EvC, EvD, EwC A/B Outwash 1 Indianola InC, InA, InD A Outwash 1 Kitsa K B, C, K C Till Klaus KsC C Outwash 1 Neilton NeC A Outwash 1 Newbe N B Till 3 Nooksack Nk C Till , 3 Norma No D Till rcas Or D Wettan Oridia Os D Till 3 Ovall OvC, OvD, OvF C Till 2 Pilchuck Pc C Till 3 Pu et Pu D Till 3 Pu llu B Till 3 Ra nar RaC, RaD, RaC, RaE B Outwash 1 Renton Re D Till 3 Salal Sa C Till 3 Sammamish Sh D Till 3 Seattle Sk D Wetland Shalcar Sm D Till 3 Si Sn C Till 3 Snohomish So, Sr D Till 3 Sultan Su C Till 3 Tukwila u D Tilt 3 Woodinville Wo D Till 3 Notes: 1. Where outwash soils are saturated or underlain at shallow depth (a5 feet) by glacial till, they should be treated as fill soils. 2. These are bedrock soils, but calibration of HSPF by King County DNRP shows bedrock soils to have similar hydrologic response to till soils. 3_ These are alluvial soils, some of which are underlain by glacial till or have a seasonally high water table. In the absence of detailed study, these soils should be treated as fill soils. 4. Buckley soils are formed on the low -permeability Osceola mudflow. Hydrologic response is assumed to be similar to that of till soils. 4- 2003 Surface Water Design Manual 3-25 1/24/2005 SECTION 4 FLOW CONTROL & WATER QUALITY ANALYSIS & DESIGN FAME T LAKE TECHNICAL. INFORMATION REPORT Existing Site Hydrology The existing site is best described as being relatively steep with dense brush and some trees. For purposes of the hydrologic model, the site must be assumed to be fully forested, per the 2005 King County Surface Water Design Manual (KCSWDM). Much of the site will be left undisturbed, so the project will be assumed to have only one basin, who's limits will be the edge of the proposed development. Developed Site Hydrology The project proposes the construction of 13 single-family residential lots, along with the associated roadways and utilities. The project site lies within the R-8 zone in Renton, which allows 35% building coverage. For purposes of the hydrologic model included in this report, the impervious lot area will include the full 35% building coverage allowed by the zoning code, plus an additional 1,000 square feet per lot of driveway and patio area. Since one of these lots will be constructed well away from the rest of the lots, and is not tributary to the remaining lots, it will be considered to be in a separate basin from the other 12 lots. This single lot will disperse roof flows to the back -yard via splash blocks or a level spreader trench. The remaining 12 lots will discharge to a public storm drainage system, which will discharge to a biofiltration Swale for stormwater treatment. Following treatment, stormwater will discharge to May Creek. Performance Standards The City of Renton has adopted the 2005 King County Surface Water Design Manual (KCSWDM) as the design document governing stormwater. KCSWDM Section 1.2.3 (Core Requirement #3) typically requires that flow control be provided. However, this section allows a Direct Discharge Exemption for sites which lie less than'/{- mile from a major receiving water. The Fawcett property lies approximately 1,200 feet upstream of Lake Washington, and therefore, qualifies for this exemption. The downstream fiowpath from the site to Lake Washington is contained within May Creek, which, in itself, is a significant receiving body. Downstream of the Fawcett site, the 100-year floodptain for May Creek appears to be contained within, or very near to the stream channels. Based on the following hydrologic model, it appears that the total flow contribution from the project site is very small in comparison to the capacity of the stream channel. FAWCETT LAKE TECHNICAL INFORMATION REPORT Pre-Deveioaed Site Hydrola�c Till Forest3 Till Pasture' Till Grass' Outwash Forest` Outwash Pasture' Outwash Grass Wetland Impervious' -Area ._... 2.19 acres. 0.00 acres 0.00 acres 0.00 acres 0.00 acres 0.00 acres 0.00 acres 0.00 acres ----- ---------- Total - 2.19 acres Scale Factor: 1.00 Hourly Y -V Reduced Time Series: JPredev.tsf >> Compute Time Series Modify User Input File for computed Time Series [.TSF] Flow Frequency Analysis Time Series File:predev.ts£ Project location:Sea-Tac ---Annual Peak Flow Rates --- Flow Rate Rank Time of Peak (CPS) 0.138 2 2/09/01 18:00 0.038 7 1/06/02 3:00 0.102 4 2/28/03 3:00 0.004 8 3/24/04 20:00 0.061 6 1/05/05 8:00 0.106 3 1/18/06 21:00 0.089 5 11/24/06 4:00 0.177 1 1/09/08 9:00 Computed Peaks FAWCETT LAKE TECHNICAL INFORMATION REPORT ----Flow Frequency -Analysis ------- - - Peaks - - Rank Return Prob (CFS) Period 0.177 1 100.00 0.990 0.138 2 25.00 0.960 0.106 3 10.00 0.900 0.102 4 5.00 9.000 0.089 5 3.00 0.667 0.061 6 2.00 0.500 0.038 7 1.30 0.231 0.004 8 1.10 0.091 0.164 50.00 0.980 Proposed Site HyAho-lba Area ---- ? "I Forest: 0.00 acres' Till Pasture 0.00 acres Till Grassi : 0.82 acresj Outwash Forest, 0-00 acres'; Outwash Pasture 0.00 acres: Outwash Grass 0.00 acres! Wetland: 0-00 acres; impervious! 1.37 acres 2.19 acres; Scale Factor: 1.00 Hourly Reduced Time Series: IDev.tsf Compute Time Series Modify User Input File for computed Time Series [.TSF] Flow Frequency Analysis Time SeriesFile:dev.tsf Project Lollation;Sea-Tac ---Annual Peak Flow Rates— -----Flow Frequency Analysis ------- Flow Rate Rank Time of Peak Peaks Rank Return Prof] (CFS) (CF$) Period 0.405 6 2/09/01 2:00 0.821 1 100.00 0.990 0.330 8 1/05/02 16:00 0.519 2 25.00 0.960 0.487 3 2/27/03 7:00 0.487 3 10.00 0.900 0.356 7 8/26/04 2:00 0.430 4 5.00 0.800 0.429 5 10/26/04 16:00 0.429 5 3.00 0.667 0.430 4 1/18/06 16:00 0.405 6 2.00 0,500 0.519 2 10/26/06 0:00 0.356 7 1.30 0.231 0.821 1 1/09/08 6:00 0.330 B 1.10 0.091 Computed Peaks 0.720 50.00 0.980 FAWCETT LAKE - TECHNICAL INFORMATION REPORT Water Quality System Stormwater treatment will be provided through a biofiltration swale along the back of the most northwesterly lots. Step 1: Calculate Design Flow 2yr Design Flow = 0.405 cfs Water Quality Design Flow = 0.24 cfs (60% of the 2 yr Design Flow) Step 2: Calculate Swale Bottom Width n., = 0.2 y = 0.33 ft. S = 2 31 ft/ft b = 0.68 ft. Step 3: Calculate Design Flow Velocity Side Slopes (z) = 3 :1 VwQ = 0.43 ft/s Step 4: Calculate Swale Length Length = 234.19 ft. Step 5: Adjust Swale Layout. bsLove = 2 ft. ATOP = 627.85 s.f. Revised Bottom Width (blIAL) = 4.5 ft. Revised Bottom Length (LFKaL) = 96.59 ft. Adjusted Velocity (V,y(�-AD) = 0.13 ft/s Step 6: Provide Conveyance Capacity for flows higher than Qwro 100-yr Design Flow = 182 cis Mannings Coefficient (n) _ 0.06 (from KCSWDM Table 4.4.1.13) 100-yr Flow Depth = 0.24 ft. 100-yr Flow Velocity = 0.65 ft/s. Min. Swale Depth W 1 ft. Freeboard = 1.24 ft. Based on this analysis, the Swale should be 1 OD-ft. long, 1.5-ft deep, 4.'S-ft wide at the bottom, have 3:1 side slopes, and have a 1 % longitudinal slope. FAWCETT LAKE TECHNICAL INFORMATION REPORT SECTION 4 FLOW CONTROL & WATER QUALITY ANALYSIS & DESIGN FAWCETT LAKrz TECHNICAL INFORMATION REPORT �rJ`•"PRO.ECT BARN Ui7C WF i or lu ham' i r y O J L D 75 C} 75 ] 50 saole feet nowFAWCETT ALKE Mr Sa sa-or OMMuftrVkWM8oent a0*ociotas, ltC EXISTING SITE ;� at. ,a3a e�,r,v�eeuatwup r,aen iep„ t o. HYDROLOGY Apra ML R•\v.��e,-+��imins►al�n�3_m rr.,w.-e++ �,.�ar�a....,r�:,.,,.,...,,�� r,...._....rr�_s:_n�.,..._ N. 4M 0TgiR DEVELOPED SITE CONDITIONS: TOTAL BASIN AREA = 2.19 AC, c c LOT AREA (LOTS 1-12) • 1.64 AC. c 10 MAX. ROOF AREA = 0.57 AC. (35% LOT AREA PER ZONING CODE) n . DRIVEWAY/PATIO AREA = 0.28 AC. n(1000 SF/LO7 ASSUMED) n H IMPERVIOUS LOT AREA = 0.85 AC. V 1 g PAVEMENT AREA - 0.52 AC. TOTAL IMPERVIOUS AREA = 1.37 AC. ri LAWN/LANDSCAPE AREA = 0.82 AC. 75 D 75 150 stab feet v �W FAWCETT ALKE a rapg07 , Site Development Associates. LRC so • at• PROPOSED 3 Pr two SITE HYDROLOGY Qur• No. SECTION 5 CONVEYANCE SYSTEM ANALYSIS AND DESIGN FAwCETT LAKE TECHNICAL INFORMATION REPORT Conveyance System Stormwater runoff from the project site will be conveyed through an underground pipe network. Gonveyance capacity is generally only an issue when pipe networks are constructed with relatively flat grades and minimal cover. Backwater surcharge issues can also be the result of catch basins being placed near the same elevation as the maximum water surface of a downstream detention facility. The roadway slopes and storm drainage pipe slopes for this project are not likely to have backwater surcharge issues. The lowest catch basin rims for this project are at feast three feet above the maximum water surface of the pond, so no backwater surcharge issues are anticipated. A complete conveyance analysis will be provided in the final draft of the report, which will be submitted after the initial review of the project. The conveyance analysis will demonstrate that the pipe network has sufficient capacity to avoid backwater surcharging during the 100-yr storm event. FAWCETT LAKE TECHNICAL INFORMATION REPORT SECTION 6 SPECIAL REPORTS AND STUDIES FAWCETT LAKE TECHNICAL INFORMATION REPORT Special Reports and Studies None of the special reports and studies listed in Section 2.3.1.1 of the KCSWDM have been prepared for this project. FAWCETT LAKE TECHNICAL INFORMATION REPORT Other Permits . This project will require a clearing and grading permit from the City of Renton, and building permits will need to be obtained prior to home construction on the individual lots. No additional permits from other agencies are required. EAWCETT LAKE TECHNICAL INFORMATION REPORT SECTION 8 CONSTRUCTION STORMWATER POLLUTION PREVENTION PLAN ANALYSIS & DESIGN FAWCETT LAKE TECHNICAL INFORMATION REPORT CSWPPP ANALYSIS & DESIGN This section of the report, along with the Temporary Erosion and Sediment Control (TESC) Plan included in the engineering drawings, is intended to serve as the construction Stormwater Pollution Prevention Plan (SWPPP) for the project. The SWPPP is outlined in conformance with the 2001 edition of the Washington State Department of Ecology's Stormwater Management Manual for Western Washington (DOE Manual). STEPS 1&2—DATA COLLECTION & ANALYSIS The topography of the site has been described previously in this report as being relatively steep. The topography of the site is shown in the engineering planset. Underlying soils within the proposed development area have been identified previously in this report as being of the Alderwood and Norma variety. These soils are generally considered to be till soils, with moderate to high runoff potential and little capacity for infiltration. The existing ground cover at the project site consists of thick brush with some trees. STEP 3 — CONSTRUCTION SWPPP DEVELOPMENT AND IMPLEMENTATION The development and implementation of this SWPPP shall consist of 12 specific elements, as outlined in the DOE Manual. They are: 1. Mark Clearing Limits Clearing limits will be flagged or fenced by the contractor or project surveyor prior to commencement of construction activity. 2. Establish Construction Access A stabilized rock construction entrance will be installed at the entrance to the plat at the onset of construction. 3. Detain Flows Prior to significant clearing, a temporary sedimentation facility shall be constructed. A temporary sediment riser shall be installed in order to ensure proper sediment control. Once the facility is constructed, the site shall be cleared and graded, and all surface water controls shall direct runoff to this facility_ When final grading is complete and the site is stabilized, the temporary facility can be removed, and all storm drainage can be routed to the permanent facility. FAWCETT LAKE TECHNICAL INFORMATION REPORT 4. Install Sediment Controls Filter fabric fencing (silt fence) shall be installed around the downstream perimeter of the site in order to keep sediment -laden stormwater from leaving the site. The fencing shall be inspected periodically to ensure its continued effectiveness. & Stabilize Soils The temporary erosion and sediment control plan calls for the stabilization of exposed soils through mulching or hydroseeding when the soils are not to be worked for a significant period of time. The plan also calls for the establishment of permanent vegetation through hydroseeding once the site has reached final grade. 6. Protect Slopes All slopes and exposed soil faces shall be protected from storm runoff as much as is practicable. Slopes shall be planted with stabilizing vegetation if they are not to be worked for a sustained period. Otherwise, they should be covered with plastic until such time that they can be permanently stabilized. 7. Protect Drain Inlets The temporary erosion and sediment control plan calls for a filter fabric sock to be installed at all nearby catch basin inlets. Filter fabric protection shall be placed in all new catch basins as they are installed. & Stabilize Channels and Outlets All temporary interceptor swales shall contain check dams whenever a drop of 2 vertical feet occurs. Water discharged from the sedimentation facility shall outfall onto a rip -rap splash pad. 9. Control Pollutants All waste materials shall be disposed of in an approved location, in accordance with King County standards. In order to reasonably prevent a contamination event (such as a fuel spill), all major vehicle maintenance shall occur off -site to the greatest extent practicable. The contractor shall provide a vehicle staging area near the entrance to the site where all fueling and maintenance activity is likely to take place. This is intended to contain the area in which a contamination event is likely to take place. The contractor shall immediately contain and clean-up an area in which a contamination event occurs. FAwcETr LAKE TECHNICAL INFORMATION REPORT 10. Control Dewatering No significant dewatering is expected to occur during this project. 11. Maintain BMPs All BMPs should be monitored and maintained regularly to ensure adequate operation. A TESC supervisor shall be identified at the beginning of the project to provide monitoring and direct the appropriate maintenance activity. As site conditions change, all BMPs shall be updated as necessary to maintain compliance with City of Renton standards. 12. Manage the Project The project will begin with a pre -construction conference in which an on -site TESC supervisor shall be identified. The on -site supervisor shall monitor all TESC facilities regularly and maintain a log of inspections and improvements to demonstrate compliance with City of Renton standards. The project is not large enough to be effectively phased, therefore, it will be important that the entire site is in conformance with City of Renton erosion control standards at all times. The TESC supervisor shall notify the project engineer of any problems with the proposed erosion control elements, or if any revisions to the plan need to be made. Additional erosion control materials, such as filter fabric fencing, cover plastic, and straw bales, shall be kept on -site at all times in the event that an erosion control feature needs to be replaced or installed. FAWCETT LAKE TECHNICAL INFORMATION REPORT SECTION 9 BOND QUANTITIES AND FACILITY SUMMARIES FAWCErr LAKE TECHNICAL INFORMATION REPORT Bond Quantities A bond quantities worksheet will be completed and submitted in the final draft of this report. The final draft will be submitted following the City's initial review of the project. Bond quantities will be calculated using the standard King County Bond Quantities Estimate Worksheet downloaded from King County's website. FAWCETT LAKE TECHNICAL INFORMATION REPORT Facility Summary A facility summary sheet will be included in the final draft of this report. FAWCETT LAKE TECHNICAL INFORMATION REPORT SECTION 10 OPERATIONS AND MAINTENANCE FAWCETT LAKE TECHNICAL INFORMATION REPORT Operations & Maintenance This section addresses operations and maintenance concerns related to the projects proposed storm drainage features. The standard operations and maintenance recommendations listed in the 2005 ikcswdm are included in the following pages. Note that only the pages which are applicable to the proposed storm drainage features have been included. FAWCETrLAKE TECHNICAL INFORMATION REPORT NO.3 - CLOSED DETENTION SYSTEMS (PIPESITANKS) Maintenance Defect Conditions When Maintenance is Needed Results Expected When Component Maintenance Is Perforated Storage Area Plugged Air Vents One-half of the cross section of a vend Is blocked at Vents free of debris and any point with debris and sediment sediment Debris and Accumulated sediment depth exceeds 10% of the AN sediment and debris . Sediment diameter of the storage area for % length of storage removed from storage area. vault or any point depth exceeds 15% of diameter. Example: 72-inch storage tank would require cleaning when sediment reaches depth of 7 inches for more than %: length of tank. Joints Between Any Crack allowing material to be transported into All joint between tank /pipe Tank/Pipe Section facility sections are sealed Tank Pipe Berri Out Any part of tank/pipe is bent out of shape more than Tank/ pipe repaired or replaced of Shape 10% of it's design shape to design. Manhole Cover Not in Place Cover is missing or only partially in place. Any open Manhole is dosed. manhole requires maintenance. Locking Mechanism cannot be opened by one maintenance Mechanism opens with proper Mechanism Not person with proper tools. Bolts into frame have less tools. Working than'/ inch of thread (may not apply to self -lacking lids.) Cover Difficult to One maintenance person Cannot remove lid after Cover Can be removed and Remove applying 80ft of lift. Intent is to keep cover from reinstalled by one maintenance sealing off access to maintenance. person. Ladder Rungs King County Safety Office and/or maintenance person Ladder meets design standards Unsafe judges that ladder is unsafe due to missing rungs, allows maintenance person safe misalignment, rust, or cracks. access. Catch Basins See 'Catch Basins" Standards No. 5 See "Catch Basins" Standards No_ 5 FAWCETT LAKE TECHNICAL INFORMATION REPORT NO.4 - CONTROL STRUCTUREIFLOW RESTRICTOR Maintenance Dahwt Condition WMn Maintenance Is Needed Results Expected When Component Maintenance Is Performed General Trash and Debris Distance between debris bulkkip and bottom of All trash and debris removed. (includes Sediment) wi ice plate is less than 1-112 feet. Structural Damage Structure is not securely attached to manhole wall Structure securely attached to and outlet pipe structure should support at least wall and outlet pipe. 1,000 Ibs of up or down pressure. Structure is rot in upright position (allow up to Structure in correct position. 10% from plumb). Connections to outlet pipe are not watt ht and Connections to outlet pipe are show signs of rust. water tight: structure repaired or replaced and works as designed. Any holes --other than designed holes --In the Structure has no holes other structure. than designed holes. Cleanout Gate Damaged or Missing Cleanout gate is not watertight or is missing. Gate is watertight and works as designed. Gate cannot be moved up and down by one Gate moves up and down easily maintenance person. and is watertight. Chain leading to gate is rnissing or damaged. Chain is in place and works as designed. Gate is rusted over 50% of its surfece area. Gate is repaired or replaced to meet design standards.. Orifice Plate Damaged or Missing Control device Is not working properly due to Plate is in place and works as missing, out of place, or bent orifice plate. designed. Obstructions Any trash, debris, sediment, or vegetation Plate Is free of all obstructions blocking the plate. and works as designed. Overflow Pipe Obstructions Any trash or debris blocking (or having the Pipe is free of all obstructions potential of blocking) the overfiowow pipe. and works as designed. Manhole See -Closed Detention Systems' Standards No. 3 See 'Closed Detention Systems' Standards No. 3 Catch Basin See "Catch Basins" Standards No. 5 See 'Catch Basins' Standards No. 5 FAWCETT LAKE TECHNICAL INFORMATION REPORT NO.5 - CATCH BASINS Maintenance Defect Conditions When (Maintenance Is Needed Results Expected When Component Maintenance Is performed General Trash & Debris Trash or debris of more than W cubic foot which is No Trash or debris located (Includes Sediment) located immediately in front of the Catch basin Immediately in front of catch opening or is blocking capacity of the basin by basin opening. more than 10% Trash or debris (in the basin) that exceeds 1/3 the depth from the bottom of basin to invert the lowest pipe into or out of the basin. Trash or debris in any inlet or outlet pipe blocking more than 113 of its height. Dead animals or vegetation that could generate odors that could cause complaints or dangerous gases (e.g., methane). Deposits of garbage exceeding 1 cubic foot in volume Structure Damage to Comer of frame extends more than 3/4 inch past Frame and/or Top Slab curb face into the sh (If applicable). Top slab has holes larger than 2 square inches or cracks wider than 1/4 inch (intent is to make sure all material is running into basin). Frame not sitting flush on top slab, i.e., separation of more than 314 inch of the frame from the top slab. No trash or debris in the Catch basin. Inlet and outlet pipes free of trash or debris_ No dead animals or vegetation present within the catch basin. No condition present which would attract or support the breeding of insects or rodents. Frame is even with Curb. Top slab is free of holes and cracks. Frame is sitting flush on top slab. Cracks in Basin Wails/ Cracks wider than 1/2 inch and longer than 3 feet, Basin replaced or repaired to Bottom any evidence of soil particles entering catch basin design standards. through cracks, or maintenance person judges that structure is unsound. Cracks wider than 112 inch and longer than 1 foot No Cracks more than 114 Inch at the joint of any inletl outlet pipe or any evidence wide at the joint of inlet/outlet of soil particles entering catch basin through pipe. cracks. Sediment/ Basin has settled more than 1 inch or has rotated Basin replaced or repaired to Misalignment more than 2 inches out of alignment. design standards. FAWCETT LAKE TECHNICAL INFORMATION REPORT NO.5 - CATCH BASINS (COAMNE EM Maintenance Defect Conditions When Mafrrtenance Is Needed ResuEs Expsc W When Component Malnumnce is performed Fire Hazard Presence of dvarnicais such as natural gas, oil and No flammable chemicals gasoline. Imo• Vegetation Vegetation growing across and blocking more than No vegetation blocking opening 10% of the basin opening. to basin. Vegetation growing In InWouliet pipe joints that Is No vegetation or root growth more than six inches tall and less than sbc In ties present. apart Pollution Nonflammable chemicals of more than 112 cubic foot No pollution present other than per three feet of basin length. surface Sm. Catch Basin Cover Cover Not In Place Cover is missing or only partially In place. Any open Catch basin cover is dosed catch basin requires maintenance. Lockim Mechanism Mechanism cannot be opened by on maintenance Mechanism opens with proper Not Working person with proper tools. Boats into frame have less tools. than 112 inch of thread. Cover Difficult to One maintenance person cannot remove lid after Cover can be removed by one Remove applying 80 tbs. of lilt; intent is keep cover from maintenance person. seatirg off access to maintenance. Ladder Ladder Rungs udder is unsafe due to missing rungs, misalignment, Ladder meets design stardards Unsafe rust, cracks, or sharp edges. and allows maintenance person safe access. Metal Grates Grate with opening wider than 718 Inch_ Grate opening meets design (if Applicable) standards. Trash and Debris Trash and debris that Is blocking more than 20% of Grate free of trash and debris. grate surface. Damaged or Grate missing or broken member(s) of the grata. Grate is in place and meets Missing. design standards - NO. 6 DEBRIS BARRIERS (E.G., TRASH RACKS) Maintenance Defect Condition When Maintenance Is Needed Results Expected When Components Makdorrence Is Performed. General Trash and Debris Trash or debris that is pkigging more than 20% of Barrier dear to receive capacity the openings in the barrier. flour. Metal Damaged/ Missing Bars are bent out of shape more than 3 inches. Bars in place with no bends more Bars. than 314 inch. Bars are missing or entire barrier missing. Bars in place according to design. Bars are loose and rust is causing 50% deterioration Repair or replace barrier to to any part of barrier. design standards. FAWCETT LAKE TECHNICAL INFORMATION REPORT NO.10 - CONVEYANCE SYSTEMS (PIPES & DITCHES) Maintenance Defect Conditions When Maintenance is Needed Results Expected When Component Maintenance is Parkcroed Pipes SWIment & Debris Accumulated sediment that exceeds 20% of the Pipe cleaned of all sediment and diameter of the pipe. debris. Vegetation Vegetation that reduces free movement of water through pipes. Damaged Protective coating is damaged; rust is causing more than 50% deteriorakm to any part of pipe. Any dent that decreases the cross section area of pipe by more than 20%. Open Ditches Trash & Debris Trash and debris exceeds 1 cubic foot per 1,000 square feet of ditch and slopes. Sediment Accumulated sediment that exceeds 20 % of the design depth. Vegetation Vegetation that reduces free movement of water through ditches - Erosion Damage to See "Ponds' Standard No. 1 Slopes Rock Lining Out of Place Maintenance person can see native soil beneath or Missing (If the rock lining. Appiicable)- Catch Basins See "Catch Basins: Standard No. 5 Debris Barriers See "Debris Barriers' Standard No-6 (e.g., Trash Rack) FAWCETT LAKE TECHNICAL INFORMATION REPORT All vegetation removed so water flows freely through pipes. Pipe repaired or replaced. Pipe repaired or replaced. Trash and debris cleared from ditches. Ditch cleaned/ flushed of all sediment and debris so that R matches design. Water flows freely through ditches. See 'Ponds' Standard No. 1 Replace rocks to design standards. See 'Catch Basins" Standard No. 5 See 'Debris Barriers' Standard No. 6 NO.13 - WATER QUALITY FACILITIES (CONTINUED) E.) Wetvaults Maintenance Defect or Problem Condidon VOwn Yainianance is Needed Reeomrrmerlded Malnkmonce to Component Coact Problem Wetvaull Trashl Debris Trash and debris accumulated in vault, pipe Remove !rash and debris from vault. Accumulation or InIeV outlet, (includes floatabtes and non- tloatabies). Sediment Sediment accumulation in vault bottom Accumulation in Vault exceeds the depth of the sediment zone plus 6-inches. Damaged Pipes Inietl outlet piping damaged or broken and in need of repair. Access Cover Cover cannot be opened or removed, Damagedl Not especially by one person. Ventilation Ventilation area blocked or plugged Vault structure Vault: Cracks wider than 1/2-Inch and any Damaged evidence of soil particles entering the structure through the cracks, or rraintenanoef inspection personnel determines that the vault is not structurally sound_ Remove sediment from vault. . Pipe repaired ands or replaced. Pipe repaired or replaced to proper working specifications. Remove or clear blocking material from ventilation area. A specified % of the vault surface area must provide ventilation to the vault interior (see p. 6- 82 for required %). Repair cracks w kler than 1 J44rich at the joint of the Well outlet pipe. Make repairs so that vault Is structurally sound. Baffles Baffles corroding, cracking, warping and/ or Repair or replace baffles to showing signs of failure as determined by specifications. mainhwoncel inspection staff. Access udder Ladder is corroded or deteriorated, not ladder naplaceci or repaired to Damage functioning properly, missing rungs, has speciflcafons, and is safe to use as cracks andf or misaligned. Confined space determined by inspection personnel_ warning sign missing. Replace sign warning of confined space entry requirements_ FAVVCETT LAKE TECHNICAL INFORMATION REPORT Christopher Brown & Awoeiates 9688 Rainier Ave. 8. &attle, WA 98118 5981 (2O6) 722-1910 fax (206) 722-1909 c r Of 7'he Fawcett flat,, VIED a TRAFFIC IMPACT ANALYSTS for an 12-Lot Singie Family Residential Plat in the North Quadrant of City of Renton February 7th, 2007 Traffic Engineers 0 Transportation Planners The Fawcett Plat TRA FFIC IMPACT ANAL YSIS Table of Contents Purpose Location and Access 3. Scope 3, Adjacent Land Uses 4, Phasing 4. Street System 4. Traffic Characteristics 5. Horizon Year Traffic 5. Trip Generation 5. Trip Distribution & Assignment 8. Year 2008 Horizon Year Traffic 8. Capacity Analysis 8. LOS Note A 11. Traffic Mitigation Fee 11, Conclusions 12. List of Figures 1. Vicinity Map 2, 2. Current P.M. Peak Hour Traffic Volumes 6. 3. 2008 P.M. Peak Hour Traffic Volumes with the Seahawks Facility 7. 4. The Fawcett Plat P.M. Peak Hour Traffic Assignment 9. 5. 2008 P.M. Peak Hour Volumes Tire Fawcett Plat Completed 10. List of Tables I The Fawcett Plat Trip Generation 5. II Levels of Service 11. Appendix Site Plan ITE LUC 210 Summary & Data LOS Computations Corridor Accident Frequencies (3-years) Chriatophcr brown Cif Amociate8 9688 Rainier Ave. 8. &attle, WA 98118-5981 (206) 722-1910 fax (206) 722-1909 the Fawcett Plat a TRAFFIC IMPACT ANALYSIS for a 12-Lot Single family Residential Plat in the North Quadrant of the City of Renton Purpose Briefly, the purpose of this study is to determine the horizon year (2008) traffic impacts that may be anticipated with the completion of the referenced 12-lot single-family residential plat that is to be constructed on a parcel of land located in the northerly quadrant of the City of Renton. More specifically, the location of the development is on the east side of Lake Washington Boulevard about half a block north of its intersection with North 4e Street and south of the existin Pan Abode mill on the southwest quadrant of the I-405 interchange with NE 44 Street. More particularly, this traffic study is to obtain current traffic volume data on Lake Washington Boulevard and NE 44t' Street, the arterial facilities expected to be impacted by ten (10) or more p.m. peak hour trips, to derive a traffic forecast of year 2008 traffic conditions both without and with the development, include forecast traffic from the presently developing Seattle Seahawks Headquarters and Training Facility (Planning File LUA-06-073) as a part of the background traffic, and assess the traffic circulation impacts that may be produced by site related traffic. The location of the plat is shown on the Vicinity Mai, Figure 1, page 2. The trip generation data for the development is based on the 7t` edition of the Tr' Generation Manual published by the Institute of Transportation Engineers (ITE). Christopher bCOWn @r Associates 9688 12ainier Ave. 8. Seattle, WA 98118-5981 (206) 722-1910 fax (206) 727-1909 FIGURE I Vicinity Map -2- Christopher brown Cif Awociate8 9688 Rainier Avc. 6, kattle, WA 98118-5981 (206) 722-1910 Fax (206) 722-1909 It may be noted that the p.m. peak hour typically is the highest peak hour of the average weekday since it contains work, school, shopping and social -recreation travel demands. Accordingly, for residential developments, it represents the worst case when traffic congestion is at its most severe levels. This TIA bases its conclusions and recommendations on the p.m. peak hour of the average weekday. The inclusion of a background traffic growth rate for assessing horizon year volumes is in accordance with the recommended practice of the Institute of Transportation Engineers (ITE), Traffic Access and Impact Studies for Site Development Transportation Engineering, August 1988. Background traffic was obtained from the traffic impact analysis (TIA) of the previously noted Seattle Seahawks Headquarters and Training Facility prepared by The Transpo Group, Bellevue, Washington (September, 2006). This traffic study uses the p.m. peak hour trip distribution model from the Seattle Seahawks Headquarters and "Training 1-'2cility TIA. Location and Access The location of the proposed 12 new single-family residences was briefly noted earlier on page 1. As shown in the appended copy of the site plan, these lots are all placed on a single parcel of land that will access a residential street with a cul-de-sac and enter Lake Washington Boulevard in a STOP sign controlled, "Tee" intersection. Entering sight distance (ESD) to both the north and south from the proposed "Tee" intersection on Lake Washington Boulevard is in excess of 1,000 feet — more than sufficient for traffic safety purposes. The City of Renton, Department of Public Works, will define the geometric design and design standards for the plats access along with nighttime illumination requirements. Scone For the purposes of this traffic study the scope of the work considers the 12 new single- family residences in concert with the traffic generated by the Seattle Seahawks Headquarters and Training Facility. For the proposed Fawcett Plat development the key intersections expected to be impacted by 10 or more site generated p.m. peak hour trips include the following. -3- Chri8topher brown & A88ociate8 9688 Rainier Avc. & (Bcattle, WA 98118-5981 (206) 722-1910 Fax (206) 72'2-1909 NE 44"' Street at the I-405 Southbound Ramps. NE 44"' Street at Ripley Lane/Pan Abode Access Driveway. Lake Washington Boulevard at the Site Access Street These intersections are described schematically in the following traffic diagrams and are analyzed later in this study. In general, the scope of the study is to address potential design needs and/or capacity restrictions, and potential traffic safety impacts on those arterial facilities receiving ten of more p-m_ peak hour trips. Adiacent Land Uses The adjacent, presently developed land uses to the south of the plat are residential and conform to the R-8 zoning of the neighborhood. To the north, on the former Baxter Mill site is the Seattle Seahawks Headquarters and Training Facility now under construction. To the northeast, on the east side of I-405, there is a local neighborhood shopping center. Accordingly, for the immediate neighborhood, the plat will conform to the existing land uses as they have developed in the past and are currently developing. From a traffic engineering perspective this is not a conflicting land use. Phasing The project will be developed in a single phase of 12 lots. For the purposes of this study the total development is expected to be fully built -out and occupied by the end of 2008. Thus, 2008 defines the horizon year for this TIA in terms of background traffic growth, Street System The adjacent arterial street serving the site is Lake Washington Boulevard. This is a 2- lane facility with a posted speed limit of 25 mph. It has bike lanes on both sides and at the site, along its street frontage, curb, gutter and sidewalk facilities will be required. On both the Ripley Lane and I-405 SB ramp intersections STOP sign control is used. -4- Chrietopher Brown CS Awociates 9688 Rainicr Avc, 8, 8cattle, WA 98118-5981 (206) 7221910 Fax (206) t'L2-1909 The various intersection geometries, grades and related lane assignments are included in the appended level of service analyses Traffic Characteristics Current (2006) peak hour traffic volume data were obtained from the Seattle Seahawks Headquarters and Training Facility T1A, Current p.m. peak hour traffic volumes are shown schematically on Figure 2. As a traffic diagram no scale is assumed: the respective arrowheads note the direction of travel. Horizon Year Traffic Figure 3 shows the 2008 horizon year traffic forecast with the Seattle Seahawks Headquarters and Training Facility completed along with background traffic growth but without the proposed 12-Lot, Fawcett Plat residential development. The data of Figure 3 was produced from the Seattle Seahawks Headquarters and Training Facility TIA. Trip Generation Trip generation for the proposed 12-Lot, Fawcett Plat residential is based on the 7`, edition of the Institute of Transportation Engineers (ITE) Trip Generation Manual, for Land Use Code 210, the applicable reference for single-family residential developments. As a relatively small development the published average trip rates are used. -5- TABLE I Fawcett Plat Trin Generation A.W.D.T. 115 Trips/Day A.M. Inbound 2 vehicles/hour A.M. Outbound 7 vehicles/hour P.M. Inbound 8 vehicles/hour P.M. Outbound 4 vehicles/hour Chri8tvpher brown & A6awiatc8 9688 12ainicr Avc. 6. 8cattle, WA 98118-5981 ci)o (206) 722-1910 Fax (206) 722-1909 Y• Y (D � r ' 0 Site Access FIGURE 2 Current P.M. Peak Hour Traffic Volumes In r NE 44th Street Christopher brown 0 Awodatea 9688 Rainicr Ave. 8. Seattle, WA 98118-5981 (206) 722-1910 Fax • (206) 222-1909 N• r{ w @ r w O Site Access a or FIGURE 3 2008 P.M. Peak Hour Traffic Volumes with the Seahawks Facility Completed -7- o NE 44th Street Chri$topher Brown e� Associates 9688 Rainier Ave. 8. 8cattle, WA 98118-5981 (206) 722-1910 Fax (206)21909 Trip Distribution & Assignment The new traffic generated by this residential development will be distributed onto the adjacent roadway system and then onto the regional transportation network. The traffic distribution and assignment of site -generated traffic is derived from the Seattle Seahawks Headquarters and Training Facility TIA which, it may be noted, was based on the trip model prepared for the Port Quendall development prepared by CH2NUf ill. A schematic diagram showing the future design hour (p.m, peak hour) trip assignment for the subject Fawcett Plat is shown on Figure 4. Year ZOOS Horizon Year Traffic Figure 5 shows the estimated 2008 P.M. Peak Hour Tra rc Volumes with the Fawcett Plat Completed. The data is made up of the data of Figure 4, the baseline p.m. peak hour 2008 volume data developed from the Seattle Seahawks Headquarters and Training Facility TIA and Figure 4, the subject Fawcett Plat p.m. peak hour traffic assignment. The peak hour data assumes no traffic diversion due to inadequate traffic conditions (such as congestion) nor presumes any geometrically or capacity inadequate linkages by the horizon year of 2008. Capacity Analysis Capacity analysis is in accordance with the 2000 Highway Capacity Manual (HCM) publication by the Transportation Research Board. The analysis was accomplished using the software entitled HCS 3, produced by the McTrans Center at the University of Florida, and used under license to Christopher Brown, P.E. The results of the analysis are noted in Table II on the next page. When reviewing the following LOS tabulated summaries, note that the computer input -and results are included in the Appendix. The appendix computations show the average delays, maximum queue lengths and approach LOS values as well as the overall LOS values at the signalized intersection. Note that at these STOP controlled intersections only the worst leg LOS and delay and is listed. Finally, intersection comments with respect to the LOS are noted directly below Table II. -8- Chrikophcr brown (n Awociate8 9688 Rainicr Ave. 6. Bcattle, WA 98118-5981 (206) 722-1910 Fax (206) 222-1909 0� FIGURE 4 P.M. Peak Hour Traffic Assignment The Fawcett Plat Completed in Christopher brown & Awodates 9688 Rainier Ave. & 8cattic, WA 98118-5981 1W (206) 722-1910 fax. (206) 722-1909 f0 �a 0 4J On .r4 4 U3 a FIGURE 5 Site Access 2008 P.M. Peak Hour Traffic Volumes with the Fawcett Plat Completed m k w w 0 cP cc 44th Street rJ l� *:i= n C% Associate& . S. 8-5981 ai (206) 722-1909 TABLE 11 Levels of Service Intersection 2007 2008 2008 Current (W/O Project) With Project NE 44th St./I-405 SB Ramps E F F See next line. STOP Controlled intersection 41.8 sec. 53.8 sec. 54.1 sec. NE 44th St./I-405 SB Ramps B See Note A 4-Way, STOP Controlled intersection 12.6 sec. NE 44th St -/Ripley Lane/Pan Abode B C C STOP Controlled intersection 12.8 sec. 20.2 sec. 20.5 sec. Lake Washington Blvd -/Site Access NA NA B STOP Controlled intersection 10.4 sec. LOS Note A Without mitigation this intersection will continue to operate at LOS `F'. If the intersection is assumed to be operating as a 4-Way STOP, the LOS increases to `B'. The Seattle Seahawks Headquarters and Training Facility TIA does not propose any traffic mitigation apart from the mitigation fee at $75 per ADT trip. From the foregoing, clearly there are no significant impacts that will alter the level of service. Accordingly, as recommended for the Seattle Seahawks Headquarters and Training Facility the only mitigation is for the imposition of a general traffic mitigation fee at the rate of $75 per new site generated ADT. Traffic Mitigation Fee The adopted standard traffic mitigation fee at the rate of $75 per added ADT for the city's street improvement program may be anticipated at 115 Trips/Day X $75 = $8,625. -11- Christopher Brown 425 Associates 9688 Rainier Ave. S. Seattle, WA 98118-5981 (206) 722-1910 fax (206) i22-1909 Conclusions The following conclusions may be considered with respect to the proposed 12-lot single- family residential Fawcett Plat. • The development, as a single-family residential project, will conform to the neighborhood as it is currently developing. • The road network under review in this TIA includes the adjacent arterial — Lake Washington Boulevard — and NE 4e Street at both Ripley Lane/Pan Abode access driveway and NE 44"' Street at the I-405 southbound ramps that receive up to 10 p.m, peak hour trips from the development. • Based on the 7t' edition of Traffic Generation the development will generate some 115 trips per day with 9 of these trips taking place during the morning peak hour and 12 in the p.m. peak hour. • For analysis purposes the time when the project is complete and fully occupied is taken at the year 2008. This is the horizon year for the TIA. • For the horizon year the presently under construction Seattle Seahawks Headquarters and Training Facility is included in addition to the background growth rate for defining the 2008 year baseline forecast. • The traffic assignment of site -generated traffic shows 15 percent of the peak hour trips will go to and from the south along Lake Washington Boulevard and 85 percent will go the north through the 1-405 interchange.' • In the horizon year of 2008 both without or with the project the worst -case LOS will be found only at the NE 44a' Streetl1-405 southbound ramps that will be at LOS `F'. • Since the project does not cause a shift in the LOS at any of the defined intersections no mitigation measure is required although it was determined that converting this intersection to a 4-Way STOP would make a marked improvement by raising the LOS `F' to LOS `B'. • With an ADT of 115 Trips/Day per the trip generation table on page 5, the city's standard mitigation fee of $75 per new ADT will require a fee of $8,625, • A review of the Lake Washington Boulevard corridor accident data from Burnett Avenue North to Ripley Lane shows only one (1) accident in the last three (3) years. There is no reason to assume there is any accident hazard on this facility that would be exacerbated by this s-f development. • No other traffic mitigation on the local and principal arterial street network is required considering the adequacy of current and forecast traffic operations. • No other traffic mitigation measures are recommended on the basis of the findings of this traffic impact analysis. -12- Christopher brown & Associates 9688 Rainier Ave. 8. 8cattle, WA 98118-5981 (206) 722-1910 Fax (206) 722-1909 Table of Contents The Fawcett Plat Appendix Site Plan • ITE LUC 210, Single -Family Detached Housing— Definition • ITE LUC 210, Single -Family Detached Housing— weekday traffic • ITE LUC 210, Single -Family Detached Housing— a.m. peak traffic • ITE LUC 210, Single -Family Detached Housing— p.m. peak traffic NE 4e St./I-405 SB Ramps NE 44 h St./1-405 SB Ramps NE 44' St./1-405 SB Ramps NE 44 h St./I-405 SB Ramps Levels of Service Current Volumes Horizon Year w/o Project Horizon Year with Project Horizon Year with Project NE 44t' St./Ripley Lane/Pan Abode Current Volumes NE 44 h St./Ripley Lane/Pan Abode Horizon Year w/o Project NE 44 h St./Ripley Lane/Pan Abode Horizon Year with Project HP-C 1 P 1, HP -HIP 2. HP -PIP 3. 4-Way STOP 4, HP-C2P 5. HP-H2P 6. HP-P2P 7. Lake Washington Blvd,/Site Access Horizon Year w/Project HP-P3P 23. Lake Washin ton Boulevard Corridor Accident Data Christophcr Brown t Aaeociatce 9688 Rainier Ave. 8. dcatdc, WA 98118-5981 (206) 722-1910 lrax (206) T22-1909 Christopher Brown e% Associate& 9688 Rainicr Ave. S. Seattle, WA 98118-5981 4 (206) 722-1910 Fax (206) 722-1909 Land Use: 210 Single -Family Detached Housing Description Single-family detached housing includes all single-family detached homes on individual lots. A typical site surveyed Is a suburban subdivision. Additional Data The number of vehicles and residents have a high correlation with average weekday vehicle trip ends. The use of these variables Is limited, however, because the numbers of vehicles and residents was often difficult to obtain or predict. The number of dwelling units is generally used as the independent variable of choice because it is usually readily available, easy to project and has a high correlation with average weekday vehicle trip ends. This land use included data from a wide variety of units with different sizes, price ranges, locations and ages. Consequently, there was a wide variation In trips generated within this category. As expected, dwelling units that were larger in size, more expensive, or farther away from the central business district,(CBD) had a higher rate of trip generation per unit than those smaller in size, less expensive, or closer to the CBD. Other factors, such as geographic location and type of adjacent and nearby development, may also have had an effect on the site trip generation. Single-family detached units had the highest trip generation rate per dwelling unit of all residential uses, because they were the largest units in size and had more residents and more vehicles per unit than other residential land uses; they were generally located farther away from shopping centers, employment areas and other trip attractors than other residential land uses; and they generally had fewer alternate modes of transportation available, because they were typically not as concentrated as other residential land uses. The peak hour of the generator typically coincided with the peak hour of the adjacent street traffic. The. sites were surveyed from the late 1960s to the 2000s throughout the United States and Canada. Source Numbers 1, 4, 5, 6, 7, 8, 11, 12, 13, 14, 108, 110, 114, 117, 119, 157, 357, 384, 435, 550, 562, 579 16, 19, 20, 21, 26, 34, 35, 36, 38, 40, 71, 72, 84, 91, 98, 100., 105, 167, 177, 187, 192, 207, 211, 246, 275, 283, 293, 300, 319, 320, Tn'p Generation, 7th Edition 268 Institute of Transportation Engineers Single -Family Detached Housing (210) Average Vehlcle Trip Ends vs: Dwelling Units On a: Weekday Number of Studies: 350 Avg. Number of Dwelling Units: 197 Directional Distribution: 50% entering, 50% exiting rip ueneration per Liwelijing unit Average Rate Range of Rates Standard Deviation 9.57 4.31 - 21.85 3.69 uata Fiot and Equation 30,000 20,000 10100D WSJ 0 10-00 X = Number of Dwelling Units X Actual Data Points Fined Curve Fitted Curve Equation: Ln(T) = 0.92 Ln(X) + 2.71 2000 ---- Average Rate' R2 = 0.96 Trip GanaraUon, 7th Edition 269 Institute of Transportation Engineers Sln&-Family Detached Housing (210) Average Vehicle Trip Ends vs: Dwelling Units On a: Weekday, Peak Hour of Adjacent Street Traffic, One .Hour Between 7 and 9 a.m. , Number of Studies: 274 Avg. Number of Dwelling Units: 201 Directional Distribution: 25% entering, 75% exiting rip Generation per Dwelling Unit Average Rate Range of Rates Standard Deviation 0.75 0.33 - 2.27 0.90 U9 a ana 'utquation 3,00 2, 1,000 n 000 U............... ............•..__._..... . x X X ; X ................... X X x x X x x X xx € 0 1000 X = Number of Dwelling Units X Actual Data Points '-"~ Ffted Curve fitted Curare Equation T 0.70(X) + 9.43 2000 ------ ,Average Rate R2 = 0.89 3000 Trip Genaratlon, 71h Edition 270 Institute of Transportation Engineers Single -Family Detached Housing (210) Average Vehicle Trip Ends vs: Dwelling Units On a: Weekday, Peak Hour of Adjacent Street Traffic, One Hour Between 4 and 6 p.m. Number of Studies: 302 Avg. Number of Dwelling Units: 214 Directional Distribution: 63% entering, 37% exiting drip Generation per Dwelling Unit Average Rate Range of Rates Standard Deviation 1.01 0.42 - 2.98 1.05 waza viot ana taluation - I Z 31000 2.000 11000 0 0 1000 2000 3000 X = Number of Dwelling Units X Actual Data PoInts Fltted Curve ------- Averageflate Fitted Curve Equation: Ln(T) = 0.90 Ln(X) + 0.53 FL12 =:O:91 Trip Generation, 7th Edition 271 institute -of TiansportationEngineers Two -Way Stop Control Page 1 of 1 TWO-WAY STOP CONTROL SUMMARY lr.pnpral Infnrmatinn ISita Information Analyst C. V. Brown Intersection NE 44thl7-405 SB Ramps Agency/Co. Hanson Planning Ju6scliction City of Renton Date Performed 2I6/07 Analysis Year Current Analysis Time Period P.M. Peak Hour Project ID File HP-C1P EastANest Street: NE 44th Street North/South Street: 1-405 SB On & Off ramps Intersection Orientation: East-West IStudy Period hrs : 1.00 ehicle Volumes and Adjustments Major Street Eastbound Westbound ovement 1 2 3 4 5 6 L T R L T R o l u me 0 152 8 252 189 0 Peak -Hour Factor, PHF 0.92 0.92 0.92 0.92 0.92 0.92 Hourly Flow Rate, HFR 0 165 8 273 205 0 Percent HeavyVehicles 0 -- — 0 — -- Median Type Undivided RT Channelized 0 0 Lanes 0 1 0 1 1 0 Configuration TR L T ,Upstream Signal 0 0 Minor Street Northbound Southbound Movement 7 8 9 10 11 12 L T R L T R Volume 0 0 0 177 0 142 Peak -Hour Factor, PHF 0.92 0.92 0.92 0.92 1 0.92 0.92 Hourly Flow Rate, HFR 0 1 0 1 0 192 0 1 154 Percent Heavy Vehicles 0 0 0 0 0 0 Percent Grade (%) 0 0 Flared Approach N N Storage 0 0 RT Channelized 0 0 Lanes 0 0 0 1 0 1 onfi uration L R Delay, Queue Length, and Level of Service Approach EB WB Northbound Southbound Movement 1 4 7 8 9 10 11 12 Lane Configuration L L R (vph) 273 192 154 C (m) (vph) 1416 245 841 Ic 0.19 0.78 0.18 95% queue length 0.72 8.28 0.67 Control Delay 6.1 67.1 10.2 LOS A F B pproach Delay — — 41.8 pproach LOS — — E HCS2000m Copyright t 2000 University of Florida, All Rights Reserved Version 4.1 file:l/C:\WTNDOWS\TEMP\u2kF2Ea.TN P 2/6/07 Two -Way Stop Control Page 1 of 1 TWO-WAY STOP CONTROL SUMMARY General Information ISite Information Analyst C. V. Brawn Agency/Co. Hanson Planning Date Performed 216107 Analysis Time Period P.M. Peak Hour Intersection NE 44th4-405 SB Ramps Jurisdiction City of Renton 4 Analysis Year 2008 w/Seahawks Facility Project ID File HP -HIP EastlWest Street: NE 44th Street North/South Street: 1-405 SB On & Off ramps Intersection Orientation: East-West IStudy Period hrs : 1.00 Vehicle Volumes and Adjustments Maior Street Eastbound Westbound Movement 1 2 3 4 5 6 L T R L T R Volume 0 222 63 260 259 0 Peak -Hour Factor, PHF 0.94 0.94 0.94 0.94 0.94 0.94 Hourly Flow Rate, HFR 0 236 67 276 275 0 Percent Heavy Vehicles 0 -- -- 0 -- -- Median Tye Undivided RT Channelized 0 0 Lanes 0 1 0 1 1 0 Configuration TR L T Upstream Signal 1 0 1 0 Minor Street Northbound Southbound Movement 7 8 9 10 11 12 L T R L T R Volume 0 0 0 150 0 200 Peak -Hour Factor, PHF 0.94 0.94 0.94 0.94 0.94 0.94 Hourly Flow Rate, HFR 0 1 0 1 0 159 0 1 212 Percent Heavy Vehicles 0 0 1 0 0 0 0 Percent Grade (%) 0 0 Flared Approach N N Storage 0 0 RT Channelized 0 0 Lanes 0 0 0 1 0 1 Configuration L R Delay, Queue Length, and Level of Service Approach EB VVB Northbound Southbound Movement 1 4 7 8 9 10 11 12 Lane Configuration L L R (vph) 276 159 212 C (m) (vph) 1269 186 769 /c 0.22 0.85 0.28 95% queue length 0.83 10.10 1.14 Control Delay 8.6 110.2 11.5 LOS A F B pproach Delay — — 53.8 pproach LOS — - F HCS2000TM Copyright © 2000 University of Florida, All Rights Reserved Version 4.1 fil e://C:IWINDOW SITEMP1u2kF2E0. TMF 2/6/07 Two -Way Stop Control Page I of 1 TWO-WAY STOP CONTROL SUMMARY General Information Site Information Analyst C. V. Brown Intersection NE 44th/1-405 SB Ramps Agency/Co. Hanson Planning Jurisdiction City of Renton Date Performed 216107 Analysis Year 2006 w/Seahawks & Project nal sis Time Period P.M. Peak Hour Project ID File HP -PIP, no miti anon EastNVest Street: NE 44th Street North/South Street: 1-405 SB On & Off ramps Intersection Orientation: East-West IStudy Period hrs : 1.00 Vehicle Volumes and Adjustments Major Street Eastbound Westbound Movement 1 2 3 4 5 5 L T R L T R Volume 0 223 65 260 263 0 Peak -Hour Factor, PHF 0.94 0.94 0.94 0.94 0.94 0.94 Hourly Flow Rate, HFR 0 237 1 69 276 1 279 1 0 Percent Heavy Vehicles 0 1 - 0 --A -- Median Type Undivided RT Channelized 0 0 Lanes 0 1 0 1 1 0 Configuration TR L T Upstream Signal I 1 0 1 1 0 Minor Street Northbound Southbound Movement 7 8 9 10 11 12 L T R L T R Volume 0 0 0 150 0 206 Peak -Hour Factor PHF 0.94 0.94 0.94 0.94 0.94 0.94 Hourly Flow Rate, HFR 0 1 0 1 0 159 1 D 1 219 Percent Heavy Vehicles 0 0 0 0 0 0 Percent Grade (%) 0 0 Flared Approach N N Storage 0 0 RT Channelized 0 0 Lanes 0 0 0 1 1 0 1 Configuration I I L I R Delay, Queue Length, and Level of Service Approach EB WB Northbound Southbound Movement 1 4 7 8 9 10 11 12 Lane Configuration L L R (vph) 276 159 219 (m) (vph) 1266 165 765 Ic 0.22 0.86 0.29 95% queue length 0.83 10.26 1.20 Control Delay 8.6 112.7 11.6 LOS A F B Approach Delay — — 54.1 ,Approach LOS — - F HC WO0 'M Copyright © 2000 University of Florida, All Rights Reserved Version 4.1 file:/IC:IWINDOWSITEMP1u2k8384.TAP 2/7/07 All -Way Stop Control Page I of I I ALL -WAY STOP CONTROL ANALYSIS IGQneral Information [Site Information Felyst C, V. Brown 111intersection. F 44tM-405 SB Romps en /Co. anson Planning urisdiction ' of Renton Performed Falysis 216107 al sis Year IP-PIP 008 w/Seahawks & Pro ect Time Period _te M. Peak Hour Project ID 4-Way East/West Street: IVJ= 44th Street North/South Street: I-405 SS Ramps 77777 Volume Adjustments and Site Characteristics �Eproaclh Eastbound Westbound Movement L T R L T R Volume 0 223 1 65 260 263 0 %Thrus Left Lane 50 50 Approach Northbound Southbound Movement L T R L T R Volume 0 0 0 150 0 206 %Thrus Left Lane 50 50 Eastbound Westbound Northbound Southbound L1 L2 L1 L2 L1 L2 Li L2 Configuration TR L T L R PHF 1,00 1,00 1.00 1.00 1.00 Flow Rate 288 260 263 150 206 Heavy Vehicles 0 0 1 0 1 0 1 0 No. Lanes 1 2 0 2 Geometry Group 3b 5 1 Duration, T 1.00 Saturation Headway Adjustment Works heet Prop. Left -Turns 0.0 1.0 0.0 1.0 0.0 Prop. Right -Turns 0.2 0.0 0.0 0.0 1.0 Prop. Heavy Vehicle 0.0 0.0 0.0 0.0 0.0 hLT-adj 6.2 0.2 0.2 0.2 0.2 0.2 hRT-adj -0.6 -0.6 -0.6 -0.6 -0.6 -0.6 HV-adj 1, 7 1.7 1.7 1.7 1.7 1.7 adj, computed 5.78 5.78 5.78 5,78 5.78 Departure Headway and Service Time d, initial value 3.20 3.20 3.20 3.20 3.20 initial 0.26 0.23 0.23 0.13 0.18 hd, final value 5.78 5.78 5.78 5.78 5.78 final value 0.46 0,44 0.43 0.25 0.30 Move -tip time, m 1 2.0 2.3 2.0 ervice Time 1 3.8 3.6 3.8 3.6 Capacity and Level of Service Eastbound Westbound Northbound Southbound L1 L2 L1 L2 L1 L2 L1 L2 Capacity 538 510 513 400 456 Delay 13.73 13,50 12.97 11.11 N.51 LOS 8 B 8 8 8 Approach: Delay 13.73 13.23 10.77 LOS B B B Intersection Delay 12.60 Intersection LOS B 7777 HCS2DOdm Copyright 0 2000 University of Florida, All Rights Reserved Version 4.1 file:HC:IWIND0WSITEMPIu2k11E17MP 2/6/07 Two -Way Stop Control Page 1 of 1 TWO-WAY STOP CONTROL SUMMARY General Information ISite Information Analyst C. V. Brown Agency/Co. Hanson Planning Date Performed 216107 Analysis Time Period P.M. Peak Hour Intersection NE 44thlRipley LanelPan Ab. Jurisdiction City of Renton Analysis Year Current Project ID P-C2P EastMest Street: NE 44th Street North/South Street: Ripley lanelPan Abode Drive Intersection Orientation: East-West IStudy Period hrs : 1.00 Vehicle Volumes and Adjustments Major Street Eastbound Westbound Movement 1 2 3 4 5 6 L T R L T R Volume 5 136 4 8 333 25 Peak -Hour Factor, PHF 0.92 0.92 0.92 0.92 0.92 0.92 Hourly Flow Rate, HFR 5 147 4 8 361 27 Percent Heavy Vehicles 0 -- -- 0 -- -- Median Type Undivided RT Channelized 0 0 Lanes 1 0 0 1 0 Configuration L TR LTR m 5 U streai nal 0 0 Minor Street Northbound Southbound ovement 7 8 9 10 11 12 L T R L T R olume 7 0 8 17 0 7 Peak -Hour Factor PHF 0.92 0.92 0.92 0.92 0.92 0.92 Hourly Flow Rate, HFR 7 1 0 8 18 1 0 1 7 Percent Heavy Vehicles 0 0 0 0 0 0 Percent Grade (%) 1 2 Flared Approach N N Storage 0 0 RT Channelized 0 0 Lanes D 1 1 0 0 1 0 onfi uration S LTR LTR Dela Queue Length. and Level of Service pproach EB WB Northbound Southbound ovement 1 4 7 8 9 10 11 12 Lane Configuration L LTR LTR LTR (vph) 5 8 15 25 C (m) (vph) 1182 1442 605 487 /G 0.00 0.01 0.02 0.05 95% queue length 0.01 0.02 0.08 0.16 Control Delay 8.1 7.5 11.1 12.8 LOS A A B B pproach Delay — — 11.1 12.8 pproach LOS — _ B B FICS2000TM Copyright C 2000 University of Florida, All Rights Reserved Version 4.1 file://C:IWINDOWSITEMP1u2kA330.TNW 2/6/07 Two -Way Stop Control Page 1 of 1 TWO-WAY STOP CONTROL SUMMARY General Information ISite Information Analyst__ C. V. Brown enc /Co. Hanson Planning Date Performed 21+6107 Analysis Time Period P.M. Peak Hour Intersection NE 44thlRi21ey LanelPan Ab. udsdiction Ci of Renton Analysis Year 2008 w/Seahawks Fat Project ID HP-H2P EastNVest Street: NE 44th Street North/South Street: Ri !e Lane/Pan Abode Drive Intersection Orientation: East-West IStudy Period hrs : 1.00 Vehicle Volumes and Adjustments Ma -or Street Eastbound Westbound Movement 1 2 3 4 5 6 L T R L T R olume 12 165 10 10 405 44 Peak -Hour Factor, PHF 0.92 0.92 0.92 0.92 0.92 0.92 Hour! y Flow Rate, HFR 13 1 179 10 10 440 47 Percent Heavy Vehicles 0 -- — 0 -- -- Median Type Undivided RT Channelized 0 0 Lanes 1 1 0 0 1 0 Configuration L TR LTR Upstream Signal 1 0 1 0 Minor Street Northbound Southbound Movement 7 8 9 10 11 12 L T R L T R Volume 10 0 10 105 0 25 Peak -Hour Factor PHF 0.92 0.92 1 0.92 0.92 0.92 0.92 Hourly Flow Rate, HFR 10 0 10 114 0 27 Percent Heavy Vehicles 0 0 0 0 0 0 Percent Grade (°k) 1 2 Flared Approach N N Storage 0 0 RT Channelized 0 0 Lanes 1 0 1 0 1 0 1 1 0 Configuration I LTR LTR Delay,Queue Length, and Level of Service Approach EB WB Northbound Southbound Movement 1 4 7 8 9 10 11 12 Lane Configuration L LTR LTR LTR (vph) 13 10 20 141 (m)(vph) 1086 1397 480 378 Ic 0.01 0.01 0.04 0.37 95% queue length 0,04 0.02 0.13 1.76 Control Delay 8.4 7.6 12.8 20.2 LOS A A B C pproach Delay — — 12.6 20.2 pproach LOS — — B C HCS2000T M Copyright ® 2000 University of lorida, All Rights Reserved Version 4.1 file://C:IWINDOW SITEMP1u2kA330.TMP 2/6/07 Two -Way Stop Control Page 1 of 1 TWO-WAY STOP CONTROL SUMMARY General Information Site Information Analyst C. V. Brown Intersection NE 44thlRipley LanelPan Ab. enc iCo. Hanson Planning Jurisdiction City of Renton Date Performed 216107 Anal sis Year 2008 wlSeahawks & Project Analysis Time Period P.M. Peak Hour Project ID P-P2P 1=astNVest Street: NE 44th Street INorthISouth Street: Ripley LanelPan Abode Drive Intersection Orientation: East-West IStudy Period hrs : 1.00 Vehicle Volumes and Adjustments Major Street Eastbound Westbound Movement 1 2 3 4 5 6 L T R L T R Volume 12 168 16 10 412 44 Peak -Hour Factor, PHF 0,92 0.92 0.92 0.92 0.92 0.92 Hourly Flow Rate, HFR 13 182 10 1 10 1 447 47 Percent Heavy Vehicles 0 0 -- -- Median Type Undivided RT Channelized 0 0 Lanes 1 1 0 0 1 0 Configuration L TR LTR U stream Signal 0 0 Minor Street Northbound Southbound Movement 7 8 9 10 11 12 L T R L T R plume 10 0 10 105 0 25 Peak -Hour Factor, PHF 0,92 0.92 0.92 0.92 0.92 1 0.92 Hourly Flow Rate, HFR 10 0 f0 114 0 27 Percent Heavy Vehicles 0 0 0 0 0 0 Percent Grade (%) 1 2 Flared Approach N N Storage 0 0 RT Channelized 0 0 Lanes 0 1 0 0 1 0 Configuration LTR LTR Delay, Queue Length. and Level of Service pproach EB WB Northbound Southbound Movement 1 4 7 8 9 10 11 12 Lane Configuration L LTR LTR LTR (vph) 13 10 20 141 (m) (vph) 1060 1394 473 373 Ic 0.01 0.01 0.04 0.38 95% queue length 0.04 0.02 0.13 1.80 Control Delay 8.4 7.6 12.9 20.5 LOS A A B C pproach Delay — — 12.9 20.5 pproach LOS — — B C HCS2000M Copyright C 2000 University of Florida, All Rights Reserved Version 4.1 file: //C:IWINDOW SITENT\u2kA3 30. TMP 2/6/07 Two -Way Stop Control Page 1 of 1 TWO-WAY STOP CONTROL SUMMARY General Information Site Information Analyst C. V. Brown Intersection Site Access/Lake Wash. Blvd Agency/Co. Hanson Planning Jurisdiction City of Renton Date Performed 216107 Analysis Year 2008 w/Seahawks & Project nal sis Time Period P.M. Peak Hour Project ID HP-P3P East/West Street: Site Access Street North/South Street: Lake Washington Blvd. Intersection Orientation: North -South IStudy Period hrs : 1,00 ehicle Volumes and Adjustments Major Street Northbound Southbound ovement 1 2 3 4 5 6 L T R L T R olume 0 187 1 7 440 0 Peak -Hour Factor, PHF 0.92 0,92 0.92 0.92 0.92 0.92 Ho^ Flow Rate, HFR 0 1 203 1 1 7 1 478 1 0 Percent Heavy Vehicles 0 -- — 0 -- - Median Tye Undivided RT Channelized 0 0 Lanes 0 1 0 0 1 0 Configuration TR LT Upstream Signal 0 0 Minor Street Westbound Eastbound Movement 7 8 9 10 11 12 L T R L T R Volume 1 0 3 0 0 0 Peak -Hour Factor PHF 0.92 0.92 0.92 0.92 0.92 0.92 Hourly Flow Rate, HFR 1 0 3 0 0 0 Percent Heavy Vehicles 0 0 0 0 0 0 Percent Grade (%) 3 0 Flared Approach N N Storage 0 0 RT Channelized 0 0 Lanes 0 0 0 0 0 0 Configuration LR Delay, Queue Length,and Level of Service pproach NB SB Westbound Eastbound Movement 1 4 7 8 9 10 11 12 Lane Configuration LT LR (vph) 7 4 (m) (vph) 1380 665 Ic 0.01 0.01 95% queue length 0.02 0.02 Control Delay 7.6 10.4 LOS A B Approach Delay -- — 10.4 pproach LOS — -- B HCS200dm Copyright 0 2000 University of Florida, All Rights Reserved Version 4.1 file://C:IWINDOWS1TEMPlu2k350.TMP 2/6/07 :1 r. Crash Record System JB Technology Inc. Corridor Report City of Renton Monday, January 08, 2007 Corridor, LAKE WASH BLVD N from THIRTY THIRD ST. N to RIPLEY LN N Report Period: Wednesday, January 01, 2003 to Monday, July 31, 2006 SEGMENT 2006 2005 2004 OTHERS TOTALS At THIRTY THIRD ST. N 0 0 0 0 0 Between THIRTY THIRD ST. N and BURNETT AVE N 1 0 0 0 1 At BURNETT AVE N 0 0 0 0 0 Between BURNETT AVE N and THIRTY SIXTH ST_ N 0 0 0 0 0 At THIRTY SIXTH ST. N 0 0 0 0 0 Between THIRTY SIXTH ST. N and THIRTY SEVENTH ST. N 0 0 0 0 0 At THIRTY SEVENTH ST. N 0 0 0 0 0 Between THIRTY SEVENTH ST. N and THIRTY EIGHT ST. N 0 0 0 0 0 At THIRTY EIGHT ST. N 0 0 0 0 0 Between THIRTY EIGHT ST. N and FORTIETH ST. N 0 0 0 0 0 At FORTIETH ST_ N 0 0 0 0 0 Between FORTIETH ST. N and RIPLEY LN N 0 0 0 0 0 At RIPLEY LN N 0 0 0 0 0 TOTALS 1 0 0 0 1 Page 3 Crash Record System _- -JB Teehnology Ina Corridor Report City of Renton Monday, January 08, 2007 Corridor: LAKE WASH BLVD N from THIRTY THIRD ST. N to RIPLEY LN N Report period: Wednesday, January 01, 2003 to Monday, July 31, 2006 SEGMENT FATALS INJURIES PDO TOTALS At THIRTY THIRD ST. N 0/0 0/0 0 0 Between THIRTY THIRD ST. N and BURNETT AVE N 010 115 0 1 At BURNETT AVE N 0/0 010 0 0 Between BURNETT AVE N and THIRTY SIXTH ST. N 0/0 010 0 0 At THIRTY SIXTH ST. N 0/0 010 0 0 Between THIRTY SIXTH ST_ N and THIRTY SEVENTH ST. N 0/0 010 0 0 At TH I RTY SEVENTH ST. N 0/0 010 0 0 Between THIRTY SEVENTH ST. N and THIRTY EIGHT ST. N 010 0/0 0 0 At THIRTY EIGHT ST. N 010 0/0 0 0 Between THIRTY EIGHT ST. N and FORTIETH ST. N 010 010 0 0 At FORTIETH ST. N 0/0 0/0 0 0 Between FORTIETH ST. N and RIPLEY LN N 0/0 010 0 0 At RIPLEY LN N 0/0 0/0 0 0 TOTALS 010 115 0 1 Page 2 { Crash Record System J8 Technology Inc. Corridor Report City of Renton Monday, January 08, 2007 Corridor: LAKE WASH BLVD N from THIRTY THIRD ST. N to RIPLEY LN N Report Period: Wednesday, January 01, 2003 to Monday, July 31, 2006 Between THIRTY THIRD ST. N and BURNETT AVE N Case Report Day Of Crash Crash Direction Severity Tot Number Number Week Date Time Location Type of Crash Vehicle lNehilce 2 Fat Inj PDO Veh Between THIRTY THIRD ST. N and BURNETT AVE N Case Report Day Of Crash Crash Direction Severity Tot Number Number Week Date Time Location Type of Crash Vehicle 1/Vehilce 2 Fat Inj PDO Veh 06-0562 4000000 Fri 06/23/2006 12:19 PM LAKE WASH BLVD N, 530 ft. South of BURNETT Rear End SB T hru I SB Thru 5 3 Page 1